77879 has 4 divisors (see below), whose sum is σ = 79584. Its totient is φ = 76176.

The previous prime is 77867. The next prime is 77893. The reversal of 77879 is 97877.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 97877 = 13 ⋅7529.

It is a cyclic number.

It is not a de Polignac number, because 77879 - 2⁴ = 77863 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77839) 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, 782 + ... + 875.

It is an arithmetic number, because the mean of its divisors is an integer number (19896).

2⁷⁷⁸⁷⁹ is an apocalyptic number.

77879 is a deficient number, since it is larger than the sum of its proper divisors (1705).

77879 is a wasteful number, since it uses less digits than its factorization.

77879 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1704.

The product of its digits is 24696, while the sum is 38.

The square root of 77879 is about 279.0680920492. The cubic root of 77879 is about 42.7044817202.

Subtracting from 77879 its sum of digits (38), we obtain a square (77841 = 279²).

The spelling of 77879 in words is "seventy-seven thousand, eight hundred seventy-nine".