1909090909091 has 16 divisors (see below), whose sum is σ = 1941350631264. Its totient is φ = 1877135215104.

The previous prime is 1909090909069. The next prime is 1909090909093.

1909090909091 is nontrivially palindromic in base 10.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1909090909091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1909090909093) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10890065 + ... + 11063981.

It is an arithmetic number, because the mean of its divisors is an integer number (121334414454).

Almost surely, 2^{1909090909091} is an apocalyptic number.

1909090909091 is a deficient number, since it is larger than the sum of its proper divisors (32259722173).

1909090909091 is a wasteful number, since it uses less digits than its factorization.

1909090909091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174790.

The product of its (nonzero) digits is 531441, while the sum is 56.

The spelling of 1909090909091 in words is "one trillion, nine hundred nine billion, ninety million, nine hundred nine thousand, ninety-one".