909090909091 has 4 divisors (see below), whose sum is σ = 910149223000. Its totient is φ = 908032595184.

The previous prime is 909090909071. The next prime is 909090909113. The reversal of 909090909091 is 190909090909.

It is a happy number.

909090909091 is digitally balanced in base 2, 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: 190909090909 = 79 ⋅2416570771.

It is a cyclic number.

It is not a de Polignac number, because 909090909091 - 2⁷ = 909090908963 is a prime.

It is a deceptive number, since it divides R_909090909090.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (909090909011) 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, 529155666 + ... + 529157383.

It is an arithmetic number, because the mean of its divisors is an integer number (227537305750).

Almost surely, 2^909090909091 is an apocalyptic number.

909090909091 is a deficient number, since it is larger than the sum of its proper divisors (1058313909).

909090909091 is a wasteful number, since it uses less digits than its factorization.

909090909091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1058313908.

The product of its (nonzero) digits is 531441, while the sum is 55.

Multiplying 909090909091 by its sum of digits (55), we get a palindrome (50000000000005).

It can be divided in two parts, 909090 and 909091, that added together give a palindrome (1818181).

The spelling of 909090909091 in words is "nine hundred nine billion, ninety million, nine hundred nine thousand, ninety-one".