78676691 has 2 divisors, whose sum is σ = 78676692. Its totient is φ = 78676690.

The previous prime is 78676679. The next prime is 78676709. The reversal of 78676691 is 19667687.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78676691 is a prime.

It is not a weakly prime, because it can be changed into another prime (78976691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39338345 + 39338346.

It is an arithmetic number, because the mean of its divisors is an integer number (39338346).

Almost surely, 2^78676691 is an apocalyptic number.

78676691 is a deficient number, since it is larger than the sum of its proper divisors (1).

78676691 is an equidigital number, since it uses as much as digits as its factorization.

78676691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 762048, while the sum is 50.

The square root of 78676691 is about 8869.9882187069. The cubic root of 78676691 is about 428.4978975065.

It can be divided in two parts, 786 and 76691, that added together give a palindrome (77477).

The spelling of 78676691 in words is "seventy-eight million, six hundred seventy-six thousand, six hundred ninety-one".