77131 has 4 divisors (see below), whose sum is σ = 77832. Its totient is φ = 76432.

The previous prime is 77101. The next prime is 77137. The reversal of 77131 is 13177.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 77131 - 2⁷ = 77003 is a prime.

It is a super-2 number, since 2×77131² = 11898382322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 77099 and 77108.

It is not an unprimeable number, because it can be changed into a prime (77137) 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, 145 + ... + 418.

It is an arithmetic number, because the mean of its divisors is an integer number (19458).

2⁷⁷¹³¹ is an apocalyptic number.

77131 is a deficient number, since it is larger than the sum of its proper divisors (701).

77131 is a wasteful number, since it uses less digits than its factorization.

77131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 700.

The product of its digits is 147, while the sum is 19.

The square root of 77131 is about 277.7246838147. The cubic root of 77131 is about 42.5673212173.

The spelling of 77131 in words is "seventy-seven thousand, one hundred thirty-one".