19139259081 has 4 divisors (see below), whose sum is σ = 25519012112. Its totient is φ = 12759506052.

The previous prime is 19139259023. The next prime is 19139259109. The reversal of 19139259081 is 18095293191.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 19139259081 - 2¹⁰ = 19139258057 is a prime.

It is a super-2 number, since 2×19139259081² (a number of 21 digits) contains 22 as substring.

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 19139259081.

It is not an unprimeable number, because it can be changed into a prime (19139259011) 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, 3189876511 + ... + 3189876516.

It is an arithmetic number, because the mean of its divisors is an integer number (6379753028).

Almost surely, 2^19139259081 is an apocalyptic number.

It is an amenable number.

19139259081 is a deficient number, since it is larger than the sum of its proper divisors (6379753031).

19139259081 is an equidigital number, since it uses as much as digits as its factorization.

19139259081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6379753030.

The product of its (nonzero) digits is 174960, while the sum is 48.

The spelling of 19139259081 in words is "nineteen billion, one hundred thirty-nine million, two hundred fifty-nine thousand, eighty-one".