79890987 has 16 divisors (see below), whose sum is σ = 116460288. Its totient is φ = 48312480.

The previous prime is 79890971. The next prime is 79890989. The reversal of 79890987 is 78909897.

It is a happy number.

It is not a de Polignac number, because 79890987 - 2⁴ = 79890971 is a prime.

It is not an unprimeable number, because it can be changed into a prime (79890989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14193 + ... + 19005.

It is an arithmetic number, because the mean of its divisors is an integer number (7278768).

Almost surely, 2^79890987 is an apocalyptic number.

79890987 is a deficient number, since it is larger than the sum of its proper divisors (36569301).

79890987 is a wasteful number, since it uses less digits than its factorization.

79890987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5330.

The product of its (nonzero) digits is 2286144, while the sum is 57.

The square root of 79890987 is about 8938.1758206023. The cubic root of 79890987 is about 430.6911312158.

The spelling of 79890987 in words is "seventy-nine million, eight hundred ninety thousand, nine hundred eighty-seven".