9090991008 has 144 divisors (see below), whose sum is σ = 28891017792. Its totient is φ = 2687616000.

The previous prime is 9090991003. The next prime is 9090991061. The reversal of 9090991008 is 8001990909.

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

It is a super-3 number, since 3×9090991008³ (a number of 31 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (9090991003) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 94893 + ... + 164883.

It is an arithmetic number, because the mean of its divisors is an integer number (200632068).

Almost surely, 2^9090991008 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 9090991008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14445508896).

9090991008 is an abundant number, since it is smaller than the sum of its proper divisors (19800026784).

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

9090991008 is a wasteful number, since it uses less digits than its factorization.

9090991008 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70059 (or 70048 counting only the distinct ones).

The product of its (nonzero) digits is 52488, while the sum is 45.

The square root of 9090991008 is about 95346.6885004403. The cubic root of 9090991008 is about 2087.0702911656.

The spelling of 9090991008 in words is "nine billion, ninety million, nine hundred ninety-one thousand, eight".