990973901 has 4 divisors (see below), whose sum is σ = 991315392. Its totient is φ = 990632412.

The previous prime is 990973889. The next prime is 990973903. The reversal of 990973901 is 109379099.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-990973901 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (990973903) 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, 166355 + ... + 172208.

It is an arithmetic number, because the mean of its divisors is an integer number (247828848).

Almost surely, 2^990973901 is an apocalyptic number.

It is an amenable number.

990973901 is a deficient number, since it is larger than the sum of its proper divisors (341491).

990973901 is a wasteful number, since it uses less digits than its factorization.

990973901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 341490.

The product of its (nonzero) digits is 137781, while the sum is 47.

The square root of 990973901 is about 31479.7379436361. The cubic root of 990973901 is about 996.9822023921.

The spelling of 990973901 in words is "nine hundred ninety million, nine hundred seventy-three thousand, nine hundred one".