990040320 has 252 divisors, whose sum is σ = 3558908556. Its totient is φ = 263761920.

The previous prime is 990040301. The next prime is 990040327. The reversal of 990040320 is 23040099.

It can be written as a sum of positive squares in 2 ways, for example, as 504631296 + 485409024 = 22464^2 + 22032^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (990040327) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 932590 + ... + 933650.

It is an arithmetic number, because the mean of its divisors is an integer number (14122653).

Almost surely, 2^990040320 is an apocalyptic number.

990040320 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 990040320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1779454278).

990040320 is an abundant number, since it is smaller than the sum of its proper divisors (2568868236).

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

990040320 is an equidigital number, since it uses as much as digits as its factorization.

990040320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1100 (or 1071 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 27.

The square root of 990040320 is about 31464.9061654409. The cubic root of 990040320 is about 996.6690235823.

The spelling of 990040320 in words is "nine hundred ninety million, forty thousand, three hundred twenty".