91666393 has 16 divisors (see below), whose sum is σ = 118760320. Its totient is φ = 68708736.

The previous prime is 91666387. The next prime is 91666409. The reversal of 91666393 is 39366619.

It is a cyclic number.

It is not a de Polignac number, because 91666393 - 2¹³ = 91658201 is a prime.

It is not an unprimeable number, because it can be changed into a prime (91666093) 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, 24780 + ... + 28237.

It is an arithmetic number, because the mean of its divisors is an integer number (7422520).

Almost surely, 2^91666393 is an apocalyptic number.

It is an amenable number.

91666393 is a deficient number, since it is larger than the sum of its proper divisors (27093927).

91666393 is a wasteful number, since it uses less digits than its factorization.

91666393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53056.

The product of its digits is 157464, while the sum is 43.

The square root of 91666393 is about 9574.2567857772. The cubic root of 91666393 is about 450.8894227950.

The spelling of 91666393 in words is "ninety-one million, six hundred sixty-six thousand, three hundred ninety-three".