990251331099 has 8 divisors (see below), whose sum is σ = 1320960571392. Its totient is φ = 659854822440.

The previous prime is 990251331053. The next prime is 990251331143. The reversal of 990251331099 is 990133152099.

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

It is not a de Polignac number, because 990251331099 - 2²⁴ = 990234553883 is a prime.

It is not an unprimeable number, because it can be changed into a prime (990251331599) 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, 78175519 + ... + 78188184.

It is an arithmetic number, because the mean of its divisors is an integer number (165120071424).

Almost surely, 2^990251331099 is an apocalyptic number.

990251331099 is a deficient number, since it is larger than the sum of its proper divisors (330709240293).

990251331099 is a wasteful number, since it uses less digits than its factorization.

990251331099 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156365817.

The product of its (nonzero) digits is 590490, while the sum is 51.

The spelling of 990251331099 in words is "nine hundred ninety billion, two hundred fifty-one million, three hundred thirty-one thousand, ninety-nine".