990431 has 8 divisors (see below), whose sum is σ = 1089984. Its totient is φ = 894240.

The previous prime is 990397. The next prime is 990463. The reversal of 990431 is 134099.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-990431 is a prime.

It is a super-2 number, since 2×990431² = 1961907131522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 990431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (990331) 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, 200 + ... + 1421.

It is an arithmetic number, because the mean of its divisors is an integer number (136248).

2⁹⁹⁰⁴³¹ is an apocalyptic number.

990431 is a deficient number, since it is larger than the sum of its proper divisors (99553).

990431 is a wasteful number, since it uses less digits than its factorization.

990431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1681.

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 990431 is about 995.2039991881. The cubic root of 990431 is about 99.6800104926.

The spelling of 990431 in words is "nine hundred ninety thousand, four hundred thirty-one".