79878990 has 32 divisors (see below), whose sum is σ = 191961216. Its totient is φ = 21273120.

The previous prime is 79878973. The next prime is 79879061. The reversal of 79878990 is 9987897.

It is a happy number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 79878990.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32505 + ... + 34875.

It is an arithmetic number, because the mean of its divisors is an integer number (5998788).

Almost surely, 2^79878990 is an apocalyptic number.

79878990 is an abundant number, since it is smaller than the sum of its proper divisors (112082226).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

79878990 is a wasteful number, since it uses less digits than its factorization.

79878990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3504.

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

The square root of 79878990 is about 8937.5046853135. The cubic root of 79878990 is about 430.6695715867.

The spelling of 79878990 in words is "seventy-nine million, eight hundred seventy-eight thousand, nine hundred ninety".