91631255 has 4 divisors (see below), whose sum is σ = 109957512. Its totient is φ = 73305000.

The previous prime is 91631227. The next prime is 91631261. The reversal of 91631255 is 55213619.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 91631255 - 2⁸ = 91630999 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9163121 + ... + 9163130.

It is an arithmetic number, because the mean of its divisors is an integer number (27489378).

Almost surely, 2^91631255 is an apocalyptic number.

91631255 is a deficient number, since it is larger than the sum of its proper divisors (18326257).

91631255 is a wasteful number, since it uses less digits than its factorization.

91631255 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18326256.

The product of its digits is 8100, while the sum is 32.

The square root of 91631255 is about 9572.4215849491. The cubic root of 91631255 is about 450.8318030690.

The spelling of 91631255 in words is "ninety-one million, six hundred thirty-one thousand, two hundred fifty-five".