999099931 has 4 divisors (see below), whose sum is σ = 1023468264. Its totient is φ = 974731600.

The previous prime is 999099919. The next prime is 999099953. The reversal of 999099931 is 139990999.

It is a happy number.

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 999099931 - 2²¹ = 997002779 is a prime.

It is a super-2 number, since 2×999099931² = 1996401344248409522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (999099901) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12184105 + ... + 12184186.

It is an arithmetic number, because the mean of its divisors is an integer number (255867066).

Almost surely, 2^999099931 is an apocalyptic number.

999099931 is a deficient number, since it is larger than the sum of its proper divisors (24368333).

999099931 is a wasteful number, since it uses less digits than its factorization.

999099931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24368332.

The product of its (nonzero) digits is 1594323, while the sum is 58.

The square root of 999099931 is about 31608.5420574882. The cubic root of 999099931 is about 999.6998869412.

The spelling of 999099931 in words is "nine hundred ninety-nine million, ninety-nine thousand, nine hundred thirty-one".