990821160000 has 1575 divisors, whose sum is σ = 4324150203219. Its totient is φ = 223606656000.

The previous prime is 990821159981. The next prime is 990821160001. The reversal of 990821160000 is 61128099.

The square root of 990821160000 is 995400.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 2 ways, for example, as 77680378944 + 913140781056 = 278712^2 + 955584^2 .

It is a tau number, because it is divible by the number of its divisors (1575).

It is a super-2 number, since 2×990821160000² (a number of 25 digits) contains 22 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (990821160001) by changing a digit.

It is a polite number, since it can be written in 224 ways as a sum of consecutive naturals, for example, 12542039961 + ... + 12542040039.

Almost surely, 2^990821160000 is an apocalyptic number.

990821160000 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

990821160000 is the 995400-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 990821160000

990821160000 is an abundant number, since it is smaller than the sum of its proper divisors (3333329043219).

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

990821160000 is an frugal number, since it uses more digits than its factorization.

990821160000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216 (or 96 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 36.

Multiplying 990821160000 by its sum of digits (36), we get a square (35669561760000 = 5972400²).

990821160000 divided by its sum of digits (36) gives a square (27522810000 = 165900²).

Adding to 990821160000 its reverse (61128099), we get a palindrome (990882288099).

The spelling of 990821160000 in words is "nine hundred ninety billion, eight hundred twenty-one million, one hundred sixty thousand".