20213280 has 96 divisors (see below), whose sum is σ = 70761600. Its totient is φ = 5389056.

The previous prime is 20213273. The next prime is 20213293. The reversal of 20213280 is 8231202.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1981 + ... + 6659.

It is an arithmetic number, because the mean of its divisors is an integer number (737100).

Almost surely, 2^20213280 is an apocalyptic number.

20213280 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 20213280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35380800).

20213280 is an abundant number, since it is smaller than the sum of its proper divisors (50548320).

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

20213280 is a wasteful number, since it uses less digits than its factorization.

20213280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4703 (or 4689 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 20213280 is about 4495.9181487211. The cubic root of 20213280 is about 272.4032369737.

Adding to 20213280 its reverse (8231202), we get a palindrome (28444482).

The spelling of 20213280 in words is "twenty million, two hundred thirteen thousand, two hundred eighty".