91571967 has 6 divisors (see below), whose sum is σ = 132270632. Its totient is φ = 61047972.

The previous prime is 91571957. The next prime is 91572007. The reversal of 91571967 is 76917519.

It is not a de Polignac number, because 91571967 - 2⁴ = 91571951 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91571957) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5087323 + ... + 5087340.

Almost surely, 2^91571967 is an apocalyptic number.

91571967 is a deficient number, since it is larger than the sum of its proper divisors (40698665).

91571967 is a wasteful number, since it uses less digits than its factorization.

91571967 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10174669 (or 10174666 counting only the distinct ones).

The product of its digits is 119070, while the sum is 45.

The square root of 91571967 is about 9569.3242708145. The cubic root of 91571967 is about 450.7345484703.

The spelling of 91571967 in words is "ninety-one million, five hundred seventy-one thousand, nine hundred sixty-seven".