99691531 has 4 divisors (see below), whose sum is σ = 103129200. Its totient is φ = 96253864.

The previous prime is 99691517. The next prime is 99691547. The reversal of 99691531 is 13519699.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13519699 = 23 ⋅587813.

It is a cyclic number.

It is not a de Polignac number, because 99691531 - 2¹¹ = 99689483 is a prime.

It is a super-3 number, since 3×99691531³ (a number of 25 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (99691231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1718791 + ... + 1718848.

It is an arithmetic number, because the mean of its divisors is an integer number (25782300).

Almost surely, 2^99691531 is an apocalyptic number.

99691531 is a deficient number, since it is larger than the sum of its proper divisors (3437669).

99691531 is a wasteful number, since it uses less digits than its factorization.

99691531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3437668.

The product of its digits is 65610, while the sum is 43.

The square root of 99691531 is about 9984.5646374792. The cubic root of 99691531 is about 463.6811296947.

The spelling of 99691531 in words is "ninety-nine million, six hundred ninety-one thousand, five hundred thirty-one".