77777131 has 2 divisors, whose sum is σ = 77777132. Its totient is φ = 77777130.

The previous prime is 77777113. The next prime is 77777177. The reversal of 77777131 is 13177777.

Together with previous prime (77777113) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 77777131 - 2⁷ = 77777003 is a prime.

It is a super-2 number, since 2×77777131² = 12098564213182322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (77277131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38888565 + 38888566.

It is an arithmetic number, because the mean of its divisors is an integer number (38888566).

Almost surely, 2^77777131 is an apocalyptic number.

77777131 is a deficient number, since it is larger than the sum of its proper divisors (1).

77777131 is an equidigital number, since it uses as much as digits as its factorization.

77777131 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 50421, while the sum is 40.

The square root of 77777131 is about 8819.1343679524. The cubic root of 77777131 is about 426.8585384447.

The spelling of 77777131 in words is "seventy-seven million, seven hundred seventy-seven thousand, one hundred thirty-one".