21309932 has 12 divisors (see below), whose sum is σ = 42619920. Its totient is φ = 9132816.

The previous prime is 21309913. The next prime is 21309973. The reversal of 21309932 is 23990312.

21309932 is an admirable number.

It is a super-2 number, since 2×21309932² = 908226403689248, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21309895 and 21309904.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 380507 + ... + 380562.

It is an arithmetic number, because the mean of its divisors is an integer number (3551660).

Almost surely, 2^21309932 is an apocalyptic number.

It is an amenable number.

21309932 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21309932 is a wasteful number, since it uses less digits than its factorization.

21309932 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 761080 (or 761078 counting only the distinct ones).

The product of its (nonzero) digits is 2916, while the sum is 29.

The square root of 21309932 is about 4616.2681897827. The cubic root of 21309932 is about 277.2430627732.

The spelling of 21309932 in words is "twenty-one million, three hundred nine thousand, nine hundred thirty-two".