21751679904 has 48 divisors (see below), whose sum is σ = 57106516320. Its totient is φ = 7249498880.

The previous prime is 21751679897. The next prime is 21751679951. The reversal of 21751679904 is 40997615712.

It is a tau number, because it is divible by the number of its divisors (48).

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, 912619 + ... + 936149.

It is an arithmetic number, because the mean of its divisors is an integer number (1189719090).

Almost surely, 2^21751679904 is an apocalyptic number.

21751679904 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21751679904 is an abundant number, since it is smaller than the sum of its proper divisors (35354836416).

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

21751679904 is a wasteful number, since it uses less digits than its factorization.

21751679904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33173 (or 33165 counting only the distinct ones).

The product of its (nonzero) digits is 952560, while the sum is 51.

The spelling of 21751679904 in words is "twenty-one billion, seven hundred fifty-one million, six hundred seventy-nine thousand, nine hundred four".