[go: up one dir, main page]

Search a number
-
+
21215400 = 23352191861
BaseRepresentation
bin101000011101…
…1100010101000
31110220212001120
41100323202220
520412343100
62034415240
7345220323
oct120734250
943825046
1021215400
1110a80498
127131520
13451a6bb
142b637ba
151ce10a0
hex143b8a8

21215400 has 96 divisors (see below), whose sum is σ = 69266400. Its totient is φ = 5356800.

The previous prime is 21215399. The next prime is 21215401. The reversal of 21215400 is 451212.

It is an interprime number because it is at equal distance from previous prime (21215399) and next prime (21215401).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21215400.

It is not an unprimeable number, because it can be changed into a prime (21215401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10470 + ... + 12330.

It is an arithmetic number, because the mean of its divisors is an integer number (721525).

Almost surely, 221215400 is an apocalyptic number.

21215400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21215400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34633200).

21215400 is an abundant number, since it is smaller than the sum of its proper divisors (48051000).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21215400 is a wasteful number, since it uses less digits than its factorization.

21215400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1899 (or 1890 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 15.

The square root of 21215400 is about 4606.0178028314. The cubic root of 21215400 is about 276.8325000542.

Adding to 21215400 its reverse (451212), we get a palindrome (21666612).

The spelling of 21215400 in words is "twenty-one million, two hundred fifteen thousand, four hundred".

Divisors: 1 2 3 4 5 6 8 10 12 15 19 20 24 25 30 38 40 50 57 60 75 76 95 100 114 120 150 152 190 200 228 285 300 380 456 475 570 600 760 950 1140 1425 1861 1900 2280 2850 3722 3800 5583 5700 7444 9305 11166 11400 14888 18610 22332 27915 35359 37220 44664 46525 55830 70718 74440 93050 106077 111660 139575 141436 176795 186100 212154 223320 279150 282872 353590 372200 424308 530385 558300 707180 848616 883975 1060770 1116600 1414360 1767950 2121540 2651925 3535900 4243080 5303850 7071800 10607700 21215400