78644360131 has 32 divisors (see below), whose sum is σ = 84967534080. Its totient is φ = 72573408000.

The previous prime is 78644360129. The next prime is 78644360143. The reversal of 78644360131 is 13106344687.

It is a cyclic number.

It is not a de Polignac number, because 78644360131 - 2¹ = 78644360129 is a prime.

It is a super-2 number, since 2×78644360131² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78644360111) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 32216871 + ... + 32219311.

It is an arithmetic number, because the mean of its divisors is an integer number (2655235440).

Almost surely, 2^78644360131 is an apocalyptic number.

78644360131 is a deficient number, since it is larger than the sum of its proper divisors (6323173949).

78644360131 is a wasteful number, since it uses less digits than its factorization.

78644360131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2827.

The product of its (nonzero) digits is 290304, while the sum is 43.

The spelling of 78644360131 in words is "seventy-eight billion, six hundred forty-four million, three hundred sixty thousand, one hundred thirty-one".