311897431 has 2 divisors, whose sum is σ = 311897432. Its totient is φ = 311897430.

The previous prime is 311897371. The next prime is 311897449. The reversal of 311897431 is 134798113.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 311897431 - 2⁷ = 311897303 is a prime.

It is a super-2 number, since 2×311897431² = 194560014928799522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (311897471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 155948715 + 155948716.

It is an arithmetic number, because the mean of its divisors is an integer number (155948716).

Almost surely, 2^311897431 is an apocalyptic number.

311897431 is a deficient number, since it is larger than the sum of its proper divisors (1).

311897431 is an equidigital number, since it uses as much as digits as its factorization.

311897431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18144, while the sum is 37.

The square root of 311897431 is about 17660.6180809166. The cubic root of 311897431 is about 678.1679571307.

The spelling of 311897431 in words is "three hundred eleven million, eight hundred ninety-seven thousand, four hundred thirty-one".