312402991 has 2 divisors, whose sum is σ = 312402992. Its totient is φ = 312402990.

The previous prime is 312402983. The next prime is 312403001. The reversal of 312402991 is 199204213.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 312402991 - 2³ = 312402983 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (312402901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156201495 + 156201496.

It is an arithmetic number, because the mean of its divisors is an integer number (156201496).

Almost surely, 2^312402991 is an apocalyptic number.

312402991 is a deficient number, since it is larger than the sum of its proper divisors (1).

312402991 is an equidigital number, since it uses as much as digits as its factorization.

312402991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 312402991 is about 17674.9254878203. The cubic root of 312402991 is about 678.5341774311.

The spelling of 312402991 in words is "three hundred twelve million, four hundred two thousand, nine hundred ninety-one".