91914591 has 4 divisors (see below), whose sum is σ = 122552792. Its totient is φ = 61276392.

The previous prime is 91914583. The next prime is 91914593. The reversal of 91914591 is 19541919.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19541919 = 3 ⋅6513973.

It is not a de Polignac number, because 91914591 - 2³ = 91914583 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 (91914593) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15319096 + ... + 15319101.

It is an arithmetic number, because the mean of its divisors is an integer number (30638198).

Almost surely, 2^91914591 is an apocalyptic number.

91914591 is a deficient number, since it is larger than the sum of its proper divisors (30638201).

91914591 is a wasteful number, since it uses less digits than its factorization.

91914591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30638200.

The product of its digits is 14580, while the sum is 39.

The square root of 91914591 is about 9587.2097609263. The cubic root of 91914591 is about 451.2960021958.

The spelling of 91914591 in words is "ninety-one million, nine hundred fourteen thousand, five hundred ninety-one".