21612936 has 16 divisors (see below), whose sum is σ = 54032400. Its totient is φ = 7204304.

The previous prime is 21612931. The next prime is 21612947. The reversal of 21612936 is 63921612.

It is not an unprimeable number, because it can be changed into a prime (21612931) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 450246 + ... + 450293.

It is an arithmetic number, because the mean of its divisors is an integer number (3377025).

Almost surely, 2^21612936 is an apocalyptic number.

It is an amenable number.

21612936 is an abundant number, since it is smaller than the sum of its proper divisors (32419464).

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

21612936 is a wasteful number, since it uses less digits than its factorization.

21612936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 900548 (or 900544 counting only the distinct ones).

The product of its digits is 3888, while the sum is 30.

The square root of 21612936 is about 4648.9714991598. The cubic root of 21612936 is about 278.5509148414.

The spelling of 21612936 in words is "twenty-one million, six hundred twelve thousand, nine hundred thirty-six".