21155952 has 40 divisors (see below), whose sum is σ = 57032064. Its totient is φ = 6745024.

The previous prime is 21155921. The next prime is 21155977. The reversal of 21155952 is 25955112.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8478 + ... + 10685.

Almost surely, 2^21155952 is an apocalyptic number.

It is an amenable number.

21155952 is an abundant number, since it is smaller than the sum of its proper divisors (35876112).

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

21155952 is a wasteful number, since it uses less digits than its factorization.

21155952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19197 (or 19191 counting only the distinct ones).

The product of its digits is 4500, while the sum is 30.

The square root of 21155952 is about 4599.5599789545. The cubic root of 21155952 is about 276.5736859531.

The spelling of 21155952 in words is "twenty-one million, one hundred fifty-five thousand, nine hundred fifty-two".