18717042887381 has 4 divisors (see below), whose sum is σ = 18736807453152. Its totient is φ = 18697278321612.

The previous prime is 18717042887359. The next prime is 18717042887393. The reversal of 18717042887381 is 18378824071781.

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 a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18717042887381 is a prime.

It is a super-2 number, since 2×18717042887381² (a number of 27 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 (18717042827381) 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, 9882281465 + ... + 9882283358.

It is an arithmetic number, because the mean of its divisors is an integer number (4684201863288).

Almost surely, 2^{18717042887381} is an apocalyptic number.

It is an amenable number.

18717042887381 is a deficient number, since it is larger than the sum of its proper divisors (19764565771).

18717042887381 is an equidigital number, since it uses as much as digits as its factorization.

18717042887381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19764565770.

The product of its (nonzero) digits is 33718272, while the sum is 65.

The spelling of 18717042887381 in words is "eighteen trillion, seven hundred seventeen billion, forty-two million, eight hundred eighty-seven thousand, three hundred eighty-one".