999964800 has 144 divisors (see below), whose sum is σ = 3568206330. Its totient is φ = 266649600.

The previous prime is 999964783. The next prime is 999964807. The reversal of 999964800 is 8469999.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 776402496 + 223562304 = 27864^2 + 14952^2 .

It is a tau number, because it is divible by the number of its divisors (144).

It is not an unprimeable number, because it can be changed into a prime (999964807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 11440 + ... + 46160.

Almost surely, 2^999964800 is an apocalyptic number.

999964800 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 999964800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1784103165).

999964800 is an abundant number, since it is smaller than the sum of its proper divisors (2568241530).

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

999964800 is a wasteful number, since it uses less digits than its factorization.

999964800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34751 (or 34731 counting only the distinct ones).

The product of its (nonzero) digits is 1259712, while the sum is 54.

The square root of 999964800 is about 31622.2200359178. The cubic root of 999964800 is about 999.9882665290.

The spelling of 999964800 in words is "nine hundred ninety-nine million, nine hundred sixty-four thousand, eight hundred".