312139777 has 2 divisors, whose sum is σ = 312139778. Its totient is φ = 312139776.

The previous prime is 312139769. The next prime is 312139781. The reversal of 312139777 is 777931213.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 164249856 + 147889921 = 12816^2 + 12161^2 .

It is an emirp because it is prime and its reverse (777931213) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 312139777 - 2³ = 312139769 is a prime.

It is not a weakly prime, because it can be changed into another prime (312139717) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156069888 + 156069889.

It is an arithmetic number, because the mean of its divisors is an integer number (156069889).

Almost surely, 2^312139777 is an apocalyptic number.

It is an amenable number.

312139777 is a deficient number, since it is larger than the sum of its proper divisors (1).

312139777 is an equidigital number, since it uses as much as digits as its factorization.

312139777 is an evil number, because the sum of its binary digits is even.

The product of its digits is 55566, while the sum is 40.

The square root of 312139777 is about 17667.4779467812. The cubic root of 312139777 is about 678.3435583877.

The spelling of 312139777 in words is "three hundred twelve million, one hundred thirty-nine thousand, seven hundred seventy-seven".