78679913 has 4 divisors (see below), whose sum is σ = 84732228. Its totient is φ = 72627600.

The previous prime is 78679903. The next prime is 78679957. The reversal of 78679913 is 31997687.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31997687 = 593 ⋅53959.

It can be written as a sum of positive squares in 2 ways, for example, as 25725184 + 52954729 = 5072^2 + 7277^2 .

It is a cyclic number.

It is not a de Polignac number, because 78679913 - 2²⁴ = 61902697 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (78679903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3026138 + ... + 3026163.

It is an arithmetic number, because the mean of its divisors is an integer number (21183057).

Almost surely, 2^78679913 is an apocalyptic number.

It is an amenable number.

78679913 is a deficient number, since it is larger than the sum of its proper divisors (6052315).

78679913 is a wasteful number, since it uses less digits than its factorization.

78679913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6052314.

The product of its digits is 571536, while the sum is 50.

The square root of 78679913 is about 8870.1698405386. The cubic root of 78679913 is about 428.5037467670.

The spelling of 78679913 in words is "seventy-eight million, six hundred seventy-nine thousand, nine hundred thirteen".