99917931 has 8 divisors (see below), whose sum is σ = 134517760. Its totient is φ = 65965032.

The previous prime is 99917927. The next prime is 99917933. The reversal of 99917931 is 13971999.

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

It is not a de Polignac number, because 99917931 - 2² = 99917927 is a prime.

It is a super-2 number, since 2×99917931² = 19967185870641522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (99917933) 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, 161371 + ... + 161988.

It is an arithmetic number, because the mean of its divisors is an integer number (16814720).

Almost surely, 2^99917931 is an apocalyptic number.

99917931 is a deficient number, since it is larger than the sum of its proper divisors (34599829).

99917931 is a wasteful number, since it uses less digits than its factorization.

99917931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 323465.

The product of its digits is 137781, while the sum is 48.

The square root of 99917931 is about 9995.8957077393. The cubic root of 99917931 is about 464.0318717579.

The spelling of 99917931 in words is "ninety-nine million, nine hundred seventeen thousand, nine hundred thirty-one".