19090909191 has 4 divisors (see below), whose sum is σ = 25454545592. Its totient is φ = 12727272792.

The previous prime is 19090909147. The next prime is 19090909193. The reversal of 19090909191 is 19190909091.

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

It is not a de Polignac number, because 19090909191 - 2²⁵ = 19057354759 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 19090909191.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19090909193) 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, 3181818196 + ... + 3181818201.

It is an arithmetic number, because the mean of its divisors is an integer number (6363636398).

Almost surely, 2^19090909191 is an apocalyptic number.

19090909191 is a deficient number, since it is larger than the sum of its proper divisors (6363636401).

19090909191 is an equidigital number, since it uses as much as digits as its factorization.

19090909191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6363636400.

The product of its (nonzero) digits is 59049, while the sum is 48.

The spelling of 19090909191 in words is "nineteen billion, ninety million, nine hundred nine thousand, one hundred ninety-one".