78831679 has 2 divisors, whose sum is σ = 78831680. Its totient is φ = 78831678.

The previous prime is 78831677. The next prime is 78831691. The reversal of 78831679 is 97613887.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78831679 - 2¹ = 78831677 is a prime.

It is a super-2 number, since 2×78831679² = 12428867227918082, which contains 22 as substring.

Together with 78831677, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78831671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39415839 + 39415840.

It is an arithmetic number, because the mean of its divisors is an integer number (39415840).

Almost surely, 2^78831679 is an apocalyptic number.

78831679 is a deficient number, since it is larger than the sum of its proper divisors (1).

78831679 is an equidigital number, since it uses as much as digits as its factorization.

78831679 is an evil number, because the sum of its binary digits is even.

The product of its digits is 508032, while the sum is 49.

The square root of 78831679 is about 8878.7205722446. The cubic root of 78831679 is about 428.7790840088.

The spelling of 78831679 in words is "seventy-eight million, eight hundred thirty-one thousand, six hundred seventy-nine".