91408971 has 16 divisors (see below), whose sum is σ = 124397568. Its totient is φ = 59690400.

The previous prime is 91408951. The next prime is 91408991. The reversal of 91408971 is 17980419.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (91408951) and next prime (91408991).

It is not a de Polignac number, because 91408971 - 2⁹ = 91408459 is a prime.

It is not an unprimeable number, because it can be changed into a prime (91408931) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 37201 + ... + 39581.

It is an arithmetic number, because the mean of its divisors is an integer number (7774848).

Almost surely, 2^91408971 is an apocalyptic number.

91408971 is a deficient number, since it is larger than the sum of its proper divisors (32988597).

91408971 is a wasteful number, since it uses less digits than its factorization.

91408971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2642.

The product of its (nonzero) digits is 18144, while the sum is 39.

The square root of 91408971 is about 9560.8038887951. The cubic root of 91408971 is about 450.4669572542.

The spelling of 91408971 in words is "ninety-one million, four hundred eight thousand, nine hundred seventy-one".