79890761 has 4 divisors (see below), whose sum is σ = 80788500. Its totient is φ = 78993024.

The previous prime is 79890749. The next prime is 79890781. The reversal of 79890761 is 16709897.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16709897 = 173 ⋅96589.

It can be written as a sum of positive squares in 2 ways, for example, as 52128400 + 27762361 = 7220^2 + 5269^2 .

It is a cyclic number.

It is not a de Polignac number, because 79890761 - 2²⁶ = 12781897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (79890781) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 448736 + ... + 448913.

It is an arithmetic number, because the mean of its divisors is an integer number (20197125).

Almost surely, 2^79890761 is an apocalyptic number.

It is an amenable number.

79890761 is a deficient number, since it is larger than the sum of its proper divisors (897739).

79890761 is an equidigital number, since it uses as much as digits as its factorization.

79890761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 897738.

The product of its (nonzero) digits is 190512, while the sum is 47.

The square root of 79890761 is about 8938.1631781927. The cubic root of 79890761 is about 430.6907250946.

The spelling of 79890761 in words is "seventy-nine million, eight hundred ninety thousand, seven hundred sixty-one".