990817228800 has 2304 divisors, whose sum is σ = 4650452352000. Its totient is φ = 201295134720.

The previous prime is 990817228757. The next prime is 990817228837. The reversal of 990817228800 is 8822718099.

It is a tau number, because it is divible by the number of its divisors (2304).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 3125606242 + ... + 3125606558.

It is an arithmetic number, because the mean of its divisors is an integer number (2018425500).

Almost surely, 2^990817228800 is an apocalyptic number.

990817228800 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 990817228800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2325226176000).

990817228800 is an abundant number, since it is smaller than the sum of its proper divisors (3659635123200).

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

990817228800 is a wasteful number, since it uses less digits than its factorization.

990817228800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 401 (or 370 counting only the distinct ones).

The product of its (nonzero) digits is 1161216, while the sum is 54.

The spelling of 990817228800 in words is "nine hundred ninety billion, eight hundred seventeen million, two hundred twenty-eight thousand, eight hundred".