21161448 has 144 divisors (see below), whose sum is σ = 72203040. Its totient is φ = 5480640.

The previous prime is 21161443. The next prime is 21161467. The reversal of 21161448 is 84416112.

It is a happy number.

21161448 is a `hidden beast` number, since 2 + 1 + 1 + 614 + 48 = 666.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (21161443) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 60811 + ... + 61157.

It is an arithmetic number, because the mean of its divisors is an integer number (501410).

Almost surely, 2^21161448 is an apocalyptic number.

21161448 is a gapful number since it is divisible by the number (28) 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 21161448, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36101520).

21161448 is an abundant number, since it is smaller than the sum of its proper divisors (51041592).

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

21161448 is a wasteful number, since it uses less digits than its factorization.

21161448 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 388 (or 370 counting only the distinct ones).

The product of its digits is 1536, while the sum is 27.

The square root of 21161448 is about 4600.1573886118. The cubic root of 21161448 is about 276.5976337822.

It can be divided in two parts, 21161 and 448, that added together give a square (21609 = 147²).

The spelling of 21161448 in words is "twenty-one million, one hundred sixty-one thousand, four hundred forty-eight".