18871379191 has 16 divisors (see below), whose sum is σ = 21701813760. Its totient is φ = 16074767520.

The previous prime is 18871379179. The next prime is 18871379209. The reversal of 18871379191 is 19197317881.

It is not a de Polignac number, because 18871379191 - 2⁹ = 18871378679 is a prime.

It is a super-2 number, since 2×18871379191² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18871379161) 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, 1259856 + ... + 1274746.

It is an arithmetic number, because the mean of its divisors is an integer number (1356363360).

Almost surely, 2^18871379191 is an apocalyptic number.

18871379191 is a deficient number, since it is larger than the sum of its proper divisors (2830434569).

18871379191 is a wasteful number, since it uses less digits than its factorization.

18871379191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16014.

The product of its digits is 762048, while the sum is 55.

The spelling of 18871379191 in words is "eighteen billion, eight hundred seventy-one million, three hundred seventy-nine thousand, one hundred ninety-one".