900990000 has 400 divisors, whose sum is σ = 3346928640. Its totient is φ = 231840000.

The previous prime is 900989963. The next prime is 900990007. The reversal of 900990000 is 99009.

It is a tau number, because it is divible by the number of its divisors (400).

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

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (900990007) 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 79 ways as a sum of consecutive naturals, for example, 12689965 + ... + 12690035.

Almost surely, 2^900990000 is an apocalyptic number.

900990000 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 900990000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1673464320).

900990000 is an abundant number, since it is smaller than the sum of its proper divisors (2445938640).

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

900990000 is a wasteful number, since it uses less digits than its factorization.

900990000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155 (or 128 counting only the distinct ones).

The product of its (nonzero) digits is 729, while the sum is 27.

The square root of 900990000 is about 30016.4954649939. The cubic root of 900990000 is about 965.8432676546.

The spelling of 900990000 in words is "nine hundred million, nine hundred ninety thousand".