869921979 has 16 divisors (see below), whose sum is σ = 1165766400. Its totient is φ = 577021536.

The previous prime is 869921971. The next prime is 869921993. The reversal of 869921979 is 979129968.

It is a happy number.

It is not a de Polignac number, because 869921979 - 2³ = 869921971 is a prime.

It is not an unprimeable number, because it can be changed into a prime (869921971) 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, 795357 + ... + 796449.

It is an arithmetic number, because the mean of its divisors is an integer number (72860400).

Almost surely, 2^869921979 is an apocalyptic number.

869921979 is a deficient number, since it is larger than the sum of its proper divisors (295844421).

869921979 is a wasteful number, since it uses less digits than its factorization.

869921979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2194.

The product of its digits is 4408992, while the sum is 60.

The square root of 869921979 is about 29494.4397980365. The cubic root of 869921979 is about 954.6117329225.

The spelling of 869921979 in words is "eight hundred sixty-nine million, nine hundred twenty-one thousand, nine hundred seventy-nine".