90900010091 has 4 divisors (see below), whose sum is σ = 99163647384. Its totient is φ = 82636372800.

The previous prime is 90900010079. The next prime is 90900010093. The reversal of 90900010091 is 19001000909.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90900010091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90900010093) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4131818630 + ... + 4131818651.

It is an arithmetic number, because the mean of its divisors is an integer number (24790911846).

Almost surely, 2^90900010091 is an apocalyptic number.

90900010091 is a deficient number, since it is larger than the sum of its proper divisors (8263637293).

90900010091 is a wasteful number, since it uses less digits than its factorization.

90900010091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8263637292.

The product of its (nonzero) digits is 729, while the sum is 29.

The spelling of 90900010091 in words is "ninety billion, nine hundred million, ten thousand, ninety-one".