990990398 has 16 divisors (see below), whose sum is σ = 1512775680. Its totient is φ = 486808056.

The previous prime is 990990383. The next prime is 990990431. The reversal of 990990398 is 893099099.

It is a happy number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7223 + ... + 45101.

It is an arithmetic number, because the mean of its divisors is an integer number (94548480).

Almost surely, 2^990990398 is an apocalyptic number.

990990398 is a deficient number, since it is larger than the sum of its proper divisors (521785282).

990990398 is a wasteful number, since it uses less digits than its factorization.

990990398 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38111.

The product of its (nonzero) digits is 1417176, while the sum is 56.

The square root of 990990398 is about 31479.9999682338. Note that the first 4 decimals coincide. The cubic root of 990990398 is about 996.9877347019.

The spelling of 990990398 in words is "nine hundred ninety million, nine hundred ninety thousand, three hundred ninety-eight".