12321172856 has 32 divisors (see below), whose sum is σ = 23267787840. Its totient is φ = 6116492928.

The previous prime is 12321172849. The next prime is 12321172907. The reversal of 12321172856 is 65827112321.

It is a super-2 number, since 2×12321172856² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1985150 + ... + 1991346.

It is an arithmetic number, because the mean of its divisors is an integer number (727118370).

Almost surely, 2^12321172856 is an apocalyptic number.

It is an amenable number.

12321172856 is a deficient number, since it is larger than the sum of its proper divisors (10946614984).

12321172856 is a wasteful number, since it uses less digits than its factorization.

12321172856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7943 (or 7939 counting only the distinct ones).

The product of its digits is 40320, while the sum is 38.

The spelling of 12321172856 in words is "twelve billion, three hundred twenty-one million, one hundred seventy-two thousand, eight hundred fifty-six".