91199131 has 2 divisors, whose sum is σ = 91199132. Its totient is φ = 91199130.

The previous prime is 91199111. The next prime is 91199137. The reversal of 91199131 is 13199119.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 91199131 - 2¹⁵ = 91166363 is a prime.

It is a super-2 number, since 2×91199131² = 16634562990310322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (91199137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45599565 + 45599566.

It is an arithmetic number, because the mean of its divisors is an integer number (45599566).

Almost surely, 2^91199131 is an apocalyptic number.

91199131 is a deficient number, since it is larger than the sum of its proper divisors (1).

91199131 is an equidigital number, since it uses as much as digits as its factorization.

91199131 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2187, while the sum is 34.

The square root of 91199131 is about 9549.8236109365. The cubic root of 91199131 is about 450.1219932626.

The spelling of 91199131 in words is "ninety-one million, one hundred ninety-nine thousand, one hundred thirty-one".