900091008 has 128 divisors (see below), whose sum is σ = 2728704000. Its totient is φ = 291879936.

The previous prime is 900091001. The next prime is 900091013. The reversal of 900091008 is 800190009.

It is a tau number, because it is divible by the number of its divisors (128).

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 (900091001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 124353 + ... + 131391.

It is an arithmetic number, because the mean of its divisors is an integer number (21318000).

Almost surely, 2^900091008 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 900091008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1364352000).

900091008 is an abundant number, since it is smaller than the sum of its proper divisors (1828612992).

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

900091008 is a wasteful number, since it uses less digits than its factorization.

900091008 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7099 (or 7081 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 27.

The square root of 900091008 is about 30001.5167616572. The cubic root of 900091008 is about 965.5219269376.

Subtracting from 900091008 its reverse (800190009), we obtain a palindrome (99900999).

The spelling of 900091008 in words is "nine hundred million, ninety-one thousand, eight".