990455664 has 160 divisors (see below), whose sum is σ = 2897314560. Its totient is φ = 291329280.

The previous prime is 990455657. The next prime is 990455681. The reversal of 990455664 is 466554099.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2363647 + ... + 2364065.

It is an arithmetic number, because the mean of its divisors is an integer number (18108216).

Almost surely, 2^990455664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 990455664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1448657280).

990455664 is an abundant number, since it is smaller than the sum of its proper divisors (1906858896).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

990455664 is a wasteful number, since it uses less digits than its factorization.

990455664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 500 (or 472 counting only the distinct ones).

The product of its (nonzero) digits is 1166400, while the sum is 48.

The square root of 990455664 is about 31471.5055883890. The cubic root of 990455664 is about 996.8083790595.

It can be divided in two parts, 990 and 455664, that added together give a palindrome (456654).

The spelling of 990455664 in words is "nine hundred ninety million, four hundred fifty-five thousand, six hundred sixty-four".