18701719519 has 4 divisors (see below), whose sum is σ = 21373393744. Its totient is φ = 16030045296.

The previous prime is 18701719511. The next prime is 18701719583. The reversal of 18701719519 is 91591710781.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 91591710781 = 17 ⋅5387747693.

It is a cyclic number.

It is not a de Polignac number, because 18701719519 - 2³ = 18701719511 is a prime.

It is a super-2 number, since 2×18701719519² (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 (18701719511) 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, 1335837102 + ... + 1335837115.

It is an arithmetic number, because the mean of its divisors is an integer number (5343348436).

Almost surely, 2^18701719519 is an apocalyptic number.

18701719519 is a deficient number, since it is larger than the sum of its proper divisors (2671674225).

18701719519 is an equidigital number, since it uses as much as digits as its factorization.

18701719519 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2671674224.

The product of its (nonzero) digits is 158760, while the sum is 49.

The spelling of 18701719519 in words is "eighteen billion, seven hundred one million, seven hundred nineteen thousand, five hundred nineteen".