79640356918 has 4 divisors (see below), whose sum is σ = 119460535380. Its totient is φ = 39820178458.

The previous prime is 79640356903. The next prime is 79640356921. The reversal of 79640356918 is 81965304697.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 81965304697 = 31 ⋅2644042087.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

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, 19910089228 + ... + 19910089231.

It is an arithmetic number, because the mean of its divisors is an integer number (29865133845).

Almost surely, 2^79640356918 is an apocalyptic number.

79640356918 is a deficient number, since it is larger than the sum of its proper divisors (39820178462).

79640356918 is a wasteful number, since it uses less digits than its factorization.

79640356918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39820178461.

The product of its (nonzero) digits is 9797760, while the sum is 58.

The spelling of 79640356918 in words is "seventy-nine billion, six hundred forty million, three hundred fifty-six thousand, nine hundred eighteen".