21317977976812 has 36 divisors (see below), whose sum is σ = 41007502017720. Its totient is φ = 9689700232960.

The previous prime is 21317977976797. The next prime is 21317977976833. The reversal of 21317977976812 is 21867977971312.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15977739 + ... + 17260477.

It is an arithmetic number, because the mean of its divisors is an integer number (1139097278270).

Almost surely, 2^{21317977976812} is an apocalyptic number.

21317977976812 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21317977976812 is a deficient number, since it is larger than the sum of its proper divisors (19689524040908).

21317977976812 is a wasteful number, since it uses less digits than its factorization.

21317977976812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1317102 (or 1317089 counting only the distinct ones).

The product of its digits is 112021056, while the sum is 70.

The spelling of 21317977976812 in words is "twenty-one trillion, three hundred seventeen billion, nine hundred seventy-seven million, nine hundred seventy-six thousand, eight hundred twelve".