79139986 has 4 divisors (see below), whose sum is σ = 118709982. Its totient is φ = 39569992.

The previous prime is 79139917. The next prime is 79139989. The reversal of 79139986 is 68993197.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 67749361 + 11390625 = 8231^2 + 3375^2 .

It is not an unprimeable number, because it can be changed into a prime (79139989) 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 as a sum of consecutive naturals, namely, 19784995 + ... + 19784998.

Almost surely, 2^79139986 is an apocalyptic number.

79139986 is a deficient number, since it is larger than the sum of its proper divisors (39569996).

79139986 is a wasteful number, since it uses less digits than its factorization.

79139986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39569995.

The product of its digits is 734832, while the sum is 52.

The square root of 79139986 is about 8896.0657596490. The cubic root of 79139986 is about 429.3373351725.

The spelling of 79139986 in words is "seventy-nine million, one hundred thirty-nine thousand, nine hundred eighty-six".