9000990091 has 2 divisors, whose sum is σ = 9000990092. Its totient is φ = 9000990090.

The previous prime is 9000990083. The next prime is 9000990107. The reversal of 9000990091 is 1900990009.

9000990091 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 9000990091 - 2³ = 9000990083 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 9000990091.

It is not a weakly prime, because it can be changed into another prime (9000990071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4500495045 + 4500495046.

It is an arithmetic number, because the mean of its divisors is an integer number (4500495046).

Almost surely, 2^9000990091 is an apocalyptic number.

9000990091 is a deficient number, since it is larger than the sum of its proper divisors (1).

9000990091 is an equidigital number, since it uses as much as digits as its factorization.

9000990091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6561, while the sum is 37.

The square root of 9000990091 is about 94873.5478992959. The cubic root of 9000990091 is about 2080.1600970058.

The spelling of 9000990091 in words is "nine billion, nine hundred ninety thousand, ninety-one".