21712725072 has 60 divisors (see below), whose sum is σ = 60780318144. Its totient is φ = 7235807040.

The previous prime is 21712725049. The next prime is 21712725077. The reversal of 21712725072 is 27052721712.

It is a happy number.

21712725072 is a `hidden beast` number, since 21 + 7 + 127 + 2 + 507 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21712725077) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 659433 + ... + 691575.

Almost surely, 2^21712725072 is an apocalyptic number.

It is an amenable number.

21712725072 is an abundant number, since it is smaller than the sum of its proper divisors (39067593072).

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

21712725072 is a wasteful number, since it uses less digits than its factorization.

21712725072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36848 (or 36839 counting only the distinct ones).

The product of its (nonzero) digits is 27440, while the sum is 36.

The spelling of 21712725072 in words is "twenty-one billion, seven hundred twelve million, seven hundred twenty-five thousand, seventy-two".