18709278719 has 4 divisors (see below), whose sum is σ = 19809824544. Its totient is φ = 17608732896.

The previous prime is 18709278691. The next prime is 18709278743. The reversal of 18709278719 is 91787290781.

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

It is a cyclic number.

It is not a de Polignac number, because 18709278719 - 2²⁰ = 18708230143 is a prime.

It is a super-2 number, since 2×18709278719² (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 (18709278779) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 550272887 + ... + 550272920.

It is an arithmetic number, because the mean of its divisors is an integer number (4952456136).

Almost surely, 2^18709278719 is an apocalyptic number.

18709278719 is a deficient number, since it is larger than the sum of its proper divisors (1100545825).

18709278719 is a wasteful number, since it uses less digits than its factorization.

18709278719 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1100545824.

The product of its (nonzero) digits is 3556224, while the sum is 59.

The spelling of 18709278719 in words is "eighteen billion, seven hundred nine million, two hundred seventy-eight thousand, seven hundred nineteen".