91693561 has 4 divisors (see below), whose sum is σ = 92173824. Its totient is φ = 91213300.

The previous prime is 91693519. The next prime is 91693573. The reversal of 91693561 is 16539619.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 16539619 = 3911 ⋅4229.

It is a cyclic number.

It is not a de Polignac number, because 91693561 - 2²⁵ = 58139129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91697561) 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, 239845 + ... + 240226.

It is an arithmetic number, because the mean of its divisors is an integer number (23043456).

Almost surely, 2^91693561 is an apocalyptic number.

It is an amenable number.

91693561 is a deficient number, since it is larger than the sum of its proper divisors (480263).

91693561 is a wasteful number, since it uses less digits than its factorization.

91693561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 480262.

The product of its digits is 43740, while the sum is 40.

The square root of 91693561 is about 9575.6754853117. The cubic root of 91693561 is about 450.9339631238.

The spelling of 91693561 in words is "ninety-one million, six hundred ninety-three thousand, five hundred sixty-one".