21712512 has 32 divisors (see below), whose sum is σ = 57674880. Its totient is φ = 7237376.

The previous prime is 21712477. The next prime is 21712513. The reversal of 21712512 is 21521712.

It is a tau number, because it is divible by the number of its divisors (32).

It is not an unprimeable number, because it can be changed into a prime (21712513) 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, 27888 + ... + 28655.

It is an arithmetic number, because the mean of its divisors is an integer number (1802340).

Almost surely, 2^21712512 is an apocalyptic number.

It is an amenable number.

21712512 is an abundant number, since it is smaller than the sum of its proper divisors (35962368).

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

21712512 is an equidigital number, since it uses as much as digits as its factorization.

21712512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56560 (or 56548 counting only the distinct ones).

The product of its digits is 280, while the sum is 21.

The square root of 21712512 is about 4659.6686577481. The cubic root of 21712512 is about 278.9780432612.

The spelling of 21712512 in words is "twenty-one million, seven hundred twelve thousand, five hundred twelve".