21506974512 has 40 divisors (see below), whose sum is σ = 55997177856. Its totient is φ = 7112540736.

The previous prime is 21506974507. The next prime is 21506974529. The reversal of 21506974512 is 21547960512.

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, 1757928 + ... + 1770119.

Almost surely, 2^21506974512 is an apocalyptic number.

It is an amenable number.

21506974512 is an abundant number, since it is smaller than the sum of its proper divisors (34490203344).

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

21506974512 is a wasteful number, since it uses less digits than its factorization.

21506974512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3528185 (or 3528179 counting only the distinct ones).

The product of its (nonzero) digits is 151200, while the sum is 42.

The spelling of 21506974512 in words is "twenty-one billion, five hundred six million, nine hundred seventy-four thousand, five hundred twelve".