77851393123931 has 16 divisors (see below), whose sum is σ = 89009798870016. Its totient is φ = 66702185221056.

The previous prime is 77851393123909. The next prime is 77851393123949. The reversal of 77851393123931 is 13932139315877.

It is a happy number.

It is not a de Polignac number, because 77851393123931 - 2²² = 77851388929627 is a prime.

It is a super-2 number, since 2×77851393123931² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77851393123951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 302022455 + ... + 302280111.

It is an arithmetic number, because the mean of its divisors is an integer number (5563112429376).

Almost surely, 2^{77851393123931} is an apocalyptic number.

77851393123931 is a deficient number, since it is larger than the sum of its proper divisors (11158405746085).

77851393123931 is a wasteful number, since it uses less digits than its factorization.

77851393123931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 275338.

The product of its digits is 25719120, while the sum is 62.

The spelling of 77851393123931 in words is "seventy-seven trillion, eight hundred fifty-one billion, three hundred ninety-three million, one hundred twenty-three thousand, nine hundred thirty-one".