78115131 has 16 divisors (see below), whose sum is σ = 115862400. Its totient is φ = 52015464.

The previous prime is 78115129. The next prime is 78115151. The reversal of 78115131 is 13151187.

It is not a de Polignac number, because 78115131 - 2¹ = 78115129 is a prime.

It is a super-2 number, since 2×78115131² = 12203947382294322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 78115095 and 78115104.

It is not an unprimeable number, because it can be changed into a prime (78115111) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42820 + ... + 44606.

It is an arithmetic number, because the mean of its divisors is an integer number (7241400).

Almost surely, 2^78115131 is an apocalyptic number.

78115131 is a deficient number, since it is larger than the sum of its proper divisors (37747269).

78115131 is a wasteful number, since it uses less digits than its factorization.

78115131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3415 (or 3409 counting only the distinct ones).

The product of its digits is 840, while the sum is 27.

The square root of 78115131 is about 8838.2764722541. The cubic root of 78115131 is about 427.4759851084.

The spelling of 78115131 in words is "seventy-eight million, one hundred fifteen thousand, one hundred thirty-one".