90999999999 has 24 divisors (see below), whose sum is σ = 133061745024. Its totient is φ = 59923080000.

The previous prime is 90999999973. The next prime is 91000000037. The reversal of 90999999999 is 99999999909.

It is not a de Polignac number, because 90999999999 - 2¹⁵ = 90999967231 is a prime.

90999999999 is a modest number, since divided by 999999 gives 90999 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90999999919) 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, 263794 + ... + 501584.

It is an arithmetic number, because the mean of its divisors is an integer number (5544239376).

Almost surely, 2^90999999999 is an apocalyptic number.

90999999999 is a deficient number, since it is larger than the sum of its proper divisors (42061745025).

90999999999 is a wasteful number, since it uses less digits than its factorization.

90999999999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 238319 (or 238316 counting only the distinct ones).

The product of its (nonzero) digits is 3486784401, while the sum is 90.

Subtracting from 90999999999 its sum of digits (90), we obtain a palindrome (90999999909).

The spelling of 90999999999 in words is "ninety billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred ninety-nine".