99668591 has 8 divisors (see below), whose sum is σ = 113457024. Its totient is φ = 86668120.

The previous prime is 99668561. The next prime is 99668629. The reversal of 99668591 is 19586699.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 99668591 - 2²⁶ = 32559727 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 (99668521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 196721 + ... + 197226.

It is an arithmetic number, because the mean of its divisors is an integer number (14182128).

Almost surely, 2^99668591 is an apocalyptic number.

99668591 is a deficient number, since it is larger than the sum of its proper divisors (13788433).

99668591 is a wasteful number, since it uses less digits than its factorization.

99668591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 393981.

The product of its digits is 1049760, while the sum is 53.

The square root of 99668591 is about 9983.4157982126. The cubic root of 99668591 is about 463.6455611063.

The spelling of 99668591 in words is "ninety-nine million, six hundred sixty-eight thousand, five hundred ninety-one".