9090910091 has 4 divisors (see below), whose sum is σ = 9098963400. Its totient is φ = 9082856784.

The previous prime is 9090910061. The next prime is 9090910133. The reversal of 9090910091 is 1900190909.

It is a happy number.

9090910091 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1900190909 = 97 ⋅19589597.

It is a cyclic number.

It is not a de Polignac number, because 9090910091 - 2³⁰ = 8017168267 is a prime.

It is a super-3 number, since 3×9090910091³ (a number of 31 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9090910061) 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, 4024961 + ... + 4027218.

It is an arithmetic number, because the mean of its divisors is an integer number (2274740850).

Almost surely, 2^9090910091 is an apocalyptic number.

9090910091 is a deficient number, since it is larger than the sum of its proper divisors (8053309).

9090910091 is a wasteful number, since it uses less digits than its factorization.

9090910091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8053308.

The product of its (nonzero) digits is 6561, while the sum is 38.

The square root of 9090910091 is about 95346.2641690801. The cubic root of 9090910091 is about 2087.0640989559.

The spelling of 9090910091 in words is "nine billion, ninety million, nine hundred ten thousand, ninety-one".