91631849 has 2 divisors, whose sum is σ = 91631850. Its totient is φ = 91631848.

The previous prime is 91631809. The next prime is 91631873. The reversal of 91631849 is 94813619.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 85895824 + 5736025 = 9268^2 + 2395^2 .

It is a cyclic number.

It is not a de Polignac number, because 91631849 - 2⁸ = 91631593 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (91631809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45815924 + 45815925.

It is an arithmetic number, because the mean of its divisors is an integer number (45815925).

Almost surely, 2^91631849 is an apocalyptic number.

It is an amenable number.

91631849 is a deficient number, since it is larger than the sum of its proper divisors (1).

91631849 is an equidigital number, since it uses as much as digits as its factorization.

91631849 is an evil number, because the sum of its binary digits is even.

The product of its digits is 46656, while the sum is 41.

The square root of 91631849 is about 9572.4526115307. The cubic root of 91631849 is about 450.8327772399.

The spelling of 91631849 in words is "ninety-one million, six hundred thirty-one thousand, eight hundred forty-nine".