21279473976 has 16 divisors (see below), whose sum is σ = 53198685000. Its totient is φ = 7093157984.

The previous prime is 21279473959. The next prime is 21279473989. The reversal of 21279473976 is 67937497212.

It is a happy number.

It is a super-2 number, since 2×21279473976² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 443322351 + ... + 443322398.

Almost surely, 2^21279473976 is an apocalyptic number.

It is an amenable number.

21279473976 is an abundant number, since it is smaller than the sum of its proper divisors (31919211024).

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

21279473976 is a wasteful number, since it uses less digits than its factorization.

21279473976 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 886644758 (or 886644754 counting only the distinct ones).

The product of its digits is 8001504, while the sum is 57.

The spelling of 21279473976 in words is "twenty-one billion, two hundred seventy-nine million, four hundred seventy-three thousand, nine hundred seventy-six".