990561600 has 504 divisors, whose sum is σ = 4166542848. Its totient is φ = 218419200.

The previous prime is 990561563. The next prime is 990561643. The reversal of 990561600 is 6165099.

990561600 is a `hidden beast` number, since 9 + 90 + 561 + 6 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (504).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 3124642 + ... + 3124958.

Almost surely, 2^990561600 is an apocalyptic number.

990561600 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 990561600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2083271424).

990561600 is an abundant number, since it is smaller than the sum of its proper divisors (3175981248).

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

990561600 is a wasteful number, since it uses less digits than its factorization.

990561600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 383 (or 365 counting only the distinct ones).

The product of its (nonzero) digits is 14580, while the sum is 36.

The square root of 990561600 is about 31473.1885896552. The cubic root of 990561600 is about 996.8439162813.

The spelling of 990561600 in words is "nine hundred ninety million, five hundred sixty-one thousand, six hundred".