91868691 has 16 divisors (see below), whose sum is σ = 126355968. Its totient is φ = 59340000.

The previous prime is 91868653. The next prime is 91868713. The reversal of 91868691 is 19686819.

It is not a de Polignac number, because 91868691 - 2⁶ = 91868627 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 91868691.

It is not an unprimeable number, because it can be changed into a prime (91868191) 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, 11016 + ... + 17466.

It is an arithmetic number, because the mean of its divisors is an integer number (7897248).

Almost surely, 2^91868691 is an apocalyptic number.

91868691 is a deficient number, since it is larger than the sum of its proper divisors (34487277).

91868691 is a wasteful number, since it uses less digits than its factorization.

91868691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6602.

The product of its digits is 186624, while the sum is 48.

The square root of 91868691 is about 9584.8156476794. The cubic root of 91868691 is about 451.2208674598.

The spelling of 91868691 in words is "ninety-one million, eight hundred sixty-eight thousand, six hundred ninety-one".