20101919191 has 2 divisors, whose sum is σ = 20101919192. Its totient is φ = 20101919190.

The previous prime is 20101919179. The next prime is 20101919207. The reversal of 20101919191 is 19191910102.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20101919191 - 2²⁵ = 20068364759 is a prime.

It is a super-2 number, since 2×20101919191² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20101919111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10050959595 + 10050959596.

It is an arithmetic number, because the mean of its divisors is an integer number (10050959596).

Almost surely, 2^20101919191 is an apocalyptic number.

20101919191 is a deficient number, since it is larger than the sum of its proper divisors (1).

20101919191 is an equidigital number, since it uses as much as digits as its factorization.

20101919191 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1458, while the sum is 34.

The spelling of 20101919191 in words is "twenty billion, one hundred one million, nine hundred nineteen thousand, one hundred ninety-one".