311491091 has 2 divisors, whose sum is σ = 311491092. Its totient is φ = 311491090.

The previous prime is 311491087. The next prime is 311491099. The reversal of 311491091 is 190194113.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 311491091 - 2² = 311491087 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (311491099) 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, 155745545 + 155745546.

It is an arithmetic number, because the mean of its divisors is an integer number (155745546).

Almost surely, 2^311491091 is an apocalyptic number.

311491091 is a deficient number, since it is larger than the sum of its proper divisors (1).

311491091 is an equidigital number, since it uses as much as digits as its factorization.

311491091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 972, while the sum is 29.

The square root of 311491091 is about 17649.1102042001. The cubic root of 311491091 is about 677.8733233863.

The spelling of 311491091 in words is "three hundred eleven million, four hundred ninety-one thousand, ninety-one".