990890055 has 24 divisors (see below), whose sum is σ = 1718400528. Its totient is φ = 528210816.

The previous prime is 990890023. The next prime is 990890059. The reversal of 990890055 is 550098099.

It is not a de Polignac number, because 990890055 - 2⁵ = 990890023 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (990890059) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 114304 + ... + 122666.

It is an arithmetic number, because the mean of its divisors is an integer number (71600022).

Almost surely, 2^990890055 is an apocalyptic number.

990890055 is a deficient number, since it is larger than the sum of its proper divisors (727510473).

990890055 is a wasteful number, since it uses less digits than its factorization.

990890055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11007 (or 11004 counting only the distinct ones).

The product of its (nonzero) digits is 145800, while the sum is 45.

The square root of 990890055 is about 31478.4061699445. The cubic root of 990890055 is about 996.9540834788.

The spelling of 990890055 in words is "nine hundred ninety million, eight hundred ninety thousand, fifty-five".