79809639 has 16 divisors (see below), whose sum is σ = 130970112. Its totient is φ = 42097248.

The previous prime is 79809637. The next prime is 79809641. The reversal of 79809639 is 93690897.

It is an interprime number because it is at equal distance from previous prime (79809637) and next prime (79809641).

It is not a de Polignac number, because 79809639 - 2¹ = 79809637 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 79809591 and 79809600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79809637) 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 15 ways as a sum of consecutive naturals, for example, 145899 + ... + 146444.

It is an arithmetic number, because the mean of its divisors is an integer number (8185632).

Almost surely, 2^79809639 is an apocalyptic number.

79809639 is a deficient number, since it is larger than the sum of its proper divisors (51160473).

79809639 is a wasteful number, since it uses less digits than its factorization.

79809639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 292366.

The product of its (nonzero) digits is 734832, while the sum is 51.

The square root of 79809639 is about 8933.6240686521. The cubic root of 79809639 is about 430.5448996162.

The spelling of 79809639 in words is "seventy-nine million, eight hundred nine thousand, six hundred thirty-nine".