9000909091 has 4 divisors (see below), whose sum is σ = 9002206152. Its totient is φ = 8999612032.

The previous prime is 9000909077. The next prime is 9000909103. The reversal of 9000909091 is 1909090009.

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

It is a cyclic number.

It is not a de Polignac number, because 9000909091 - 2¹⁷ = 9000778019 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 9000909091.

It is not an unprimeable number, because it can be changed into a prime (9000909391) 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, 638065 + ... + 652018.

It is an arithmetic number, because the mean of its divisors is an integer number (2250551538).

Almost surely, 2^9000909091 is an apocalyptic number.

9000909091 is a deficient number, since it is larger than the sum of its proper divisors (1297061).

9000909091 is a wasteful number, since it uses less digits than its factorization.

9000909091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1297060.

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

The square root of 9000909091 is about 94873.1210143316. The cubic root of 9000909091 is about 2080.1538571933.

The spelling of 9000909091 in words is "nine billion, nine hundred nine thousand, ninety-one".