78634931 has 2 divisors, whose sum is σ = 78634932. Its totient is φ = 78634930.

The previous prime is 78634903. The next prime is 78634951. The reversal of 78634931 is 13943687.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78634931 - 2⁶ = 78634867 is a prime.

It is a super-2 number, since 2×78634931² = 12366904746749522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78634951) 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 as a sum of consecutive naturals, namely, 39317465 + 39317466.

It is an arithmetic number, because the mean of its divisors is an integer number (39317466).

Almost surely, 2^78634931 is an apocalyptic number.

78634931 is a deficient number, since it is larger than the sum of its proper divisors (1).

78634931 is an equidigital number, since it uses as much as digits as its factorization.

78634931 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108864, while the sum is 41.

The square root of 78634931 is about 8867.6339008780. The cubic root of 78634931 is about 428.4220714101.

The spelling of 78634931 in words is "seventy-eight million, six hundred thirty-four thousand, nine hundred thirty-one".