18739893781 has 16 divisors (see below), whose sum is σ = 23870367360. Its totient is φ = 14322216960.

The previous prime is 18739893773. The next prime is 18739893833.

18739893781 is nontrivially palindromic in base 10.

It is a cyclic number.

It is not a de Polignac number, because 18739893781 - 2³ = 18739893773 is a prime.

It is a super-2 number, since 2×18739893781² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18739893581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4141900 + ... + 4146421.

It is an arithmetic number, because the mean of its divisors is an integer number (1491897960).

Almost surely, 2^18739893781 is an apocalyptic number.

It is an amenable number.

18739893781 is a deficient number, since it is larger than the sum of its proper divisors (5130473579).

18739893781 is a wasteful number, since it uses less digits than its factorization.

18739893781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8288364.

The product of its digits is 18289152, while the sum is 64.

The spelling of 18739893781 in words is "eighteen billion, seven hundred thirty-nine million, eight hundred ninety-three thousand, seven hundred eighty-one".