21016575772 has 24 divisors (see below), whose sum is σ = 38736786816. Its totient is φ = 9957462768.

The previous prime is 21016575763. The next prime is 21016575787. The reversal of 21016575772 is 27757561012.

It is a hoax number, since the sum of its digits (43) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

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, 1057638 + ... + 1077325.

It is an arithmetic number, because the mean of its divisors is an integer number (1614032784).

Almost surely, 2^21016575772 is an apocalyptic number.

It is an amenable number.

21016575772 is a deficient number, since it is larger than the sum of its proper divisors (17720211044).

21016575772 is a wasteful number, since it uses less digits than its factorization.

21016575772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2135097 (or 2135095 counting only the distinct ones).

The product of its (nonzero) digits is 205800, while the sum is 43.

The spelling of 21016575772 in words is "twenty-one billion, sixteen million, five hundred seventy-five thousand, seven hundred seventy-two".