991090967 has 2 divisors, whose sum is σ = 991090968. Its totient is φ = 991090966.

The previous prime is 991090963. The next prime is 991091009. The reversal of 991090967 is 769090199.

It is a weak prime.

It is an emirp because it is prime and its reverse (769090199) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 991090967 - 2² = 991090963 is a prime.

It is a super-2 number, since 2×991090967² = 1964522609737990178, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (991090963) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495545483 + 495545484.

It is an arithmetic number, because the mean of its divisors is an integer number (495545484).

Almost surely, 2^991090967 is an apocalyptic number.

991090967 is a deficient number, since it is larger than the sum of its proper divisors (1).

991090967 is an equidigital number, since it uses as much as digits as its factorization.

991090967 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 275562, while the sum is 50.

The square root of 991090967 is about 31481.5972752337. The cubic root of 991090967 is about 997.0214594377.

The spelling of 991090967 in words is "nine hundred ninety-one million, ninety thousand, nine hundred sixty-seven".