79439999 has 16 divisors (see below), whose sum is σ = 85695168. Its totient is φ = 73446912.

The previous prime is 79439977. The next prime is 79440037. The reversal of 79439999 is 99993497.

It is a de Polignac number, because none of the positive numbers 2^k-79439999 is a prime.

It is a super-2 number, since 2×79439999² = 12621426882240002, which contains 22 as substring.

It is a Duffinian number.

79439999 is a modest number, since divided by 9999 gives 7943 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79439909) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 235559 + ... + 235895.

It is an arithmetic number, because the mean of its divisors is an integer number (5355948).

Almost surely, 2^79439999 is an apocalyptic number.

79439999 is a deficient number, since it is larger than the sum of its proper divisors (6255169).

79439999 is a wasteful number, since it uses less digits than its factorization.

79439999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 674.

The product of its digits is 4960116, while the sum is 59.

The square root of 79439999 is about 8912.9119259645. The cubic root of 79439999 is about 429.8791782413.

The spelling of 79439999 in words is "seventy-nine million, four hundred thirty-nine thousand, nine hundred ninety-nine".