91566971 has 4 divisors (see below), whose sum is σ = 94041792. Its totient is φ = 89092152.

The previous prime is 91566967. The next prime is 91566977. The reversal of 91566971 is 17966519.

It is a happy number.

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

It is not a de Polignac number, because 91566971 - 2² = 91566967 is a prime.

It is a super-2 number, since 2×91566971² = 16769020356229682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91566977) 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 in 3 ways as a sum of consecutive naturals, for example, 1237355 + ... + 1237428.

It is an arithmetic number, because the mean of its divisors is an integer number (23510448).

Almost surely, 2^91566971 is an apocalyptic number.

91566971 is a deficient number, since it is larger than the sum of its proper divisors (2474821).

91566971 is a wasteful number, since it uses less digits than its factorization.

91566971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2474820.

The product of its digits is 102060, while the sum is 44.

The square root of 91566971 is about 9569.0632247885. The cubic root of 91566971 is about 450.7263512354.

The spelling of 91566971 in words is "ninety-one million, five hundred sixty-six thousand, nine hundred seventy-one".