6864121656 has 128 divisors (see below), whose sum is σ = 22738406400. Its totient is φ = 1875899520.

The previous prime is 6864121651. The next prime is 6864121657. The reversal of 6864121656 is 6561214686.

It is a super-2 number, since 2×6864121656² = 94232332216736364672, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6864121651) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 63915 + ... + 133466.

It is an arithmetic number, because the mean of its divisors is an integer number (177643800).

Almost surely, 2^6864121656 is an apocalyptic number.

It is an amenable number.

6864121656 is an abundant number, since it is smaller than the sum of its proper divisors (15874284744).

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

6864121656 is a wasteful number, since it uses less digits than its factorization.

6864121656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 197426 (or 197416 counting only the distinct ones).

The product of its digits is 414720, while the sum is 45.

The square root of 6864121656 is about 82849.9949064573. The cubic root of 6864121656 is about 1900.4727960977.

The spelling of 6864121656 in words is "six billion, eight hundred sixty-four million, one hundred twenty-one thousand, six hundred fifty-six".