21279875568 has 40 divisors (see below), whose sum is σ = 62826300288. Its totient is φ = 6079964352.

The previous prime is 21279875549. The next prime is 21279875597. The reversal of 21279875568 is 86557897212.

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, 31666146 + ... + 31666817.

Almost surely, 2^21279875568 is an apocalyptic number.

21279875568 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21279875568 is an abundant number, since it is smaller than the sum of its proper divisors (41546424720).

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

21279875568 is a wasteful number, since it uses less digits than its factorization.

21279875568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63332981 (or 63332975 counting only the distinct ones).

The product of its digits is 16934400, while the sum is 60.

The spelling of 21279875568 in words is "twenty-one billion, two hundred seventy-nine million, eight hundred seventy-five thousand, five hundred sixty-eight".