99940591 has 4 divisors (see below), whose sum is σ = 100910992. Its totient is φ = 98970192.

The previous prime is 99940579. The next prime is 99940597. The reversal of 99940591 is 19504999.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 99940591 - 2²¹ = 97843439 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 (99940597) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 485046 + ... + 485251.

It is an arithmetic number, because the mean of its divisors is an integer number (25227748).

Almost surely, 2^99940591 is an apocalyptic number.

99940591 is a deficient number, since it is larger than the sum of its proper divisors (970401).

99940591 is a wasteful number, since it uses less digits than its factorization.

99940591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 970400.

The product of its (nonzero) digits is 131220, while the sum is 46.

The square root of 99940591 is about 9997.0291086902. The cubic root of 99940591 is about 464.0669477692.

The spelling of 99940591 in words is "ninety-nine million, nine hundred forty thousand, five hundred ninety-one".