18625981746817 has 4 divisors (see below), whose sum is σ = 18636957577476. Its totient is φ = 18615005916160.

The previous prime is 18625981746787. The next prime is 18625981746833. The reversal of 18625981746817 is 71864718952681.

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

It can be written as a sum of positive squares in 2 ways, for example, as 17909113031056 + 716868715761 = 4231916^2 + 846681^2 .

It is a cyclic number.

It is not a de Polignac number, because 18625981746817 - 2²⁷ = 18625847529089 is a prime.

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 18625981746817.

It is not an unprimeable number, because it can be changed into a prime (18625981746857) 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, 5487912784 + ... + 5487916177.

It is an arithmetic number, because the mean of its divisors is an integer number (4659239394369).

Almost surely, 2^{18625981746817} is an apocalyptic number.

It is an amenable number.

18625981746817 is a deficient number, since it is larger than the sum of its proper divisors (10975830659).

18625981746817 is a wasteful number, since it uses less digits than its factorization.

18625981746817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10975830658.

The product of its digits is 325140480, while the sum is 73.

The spelling of 18625981746817 in words is "eighteen trillion, six hundred twenty-five billion, nine hundred eighty-one million, seven hundred forty-six thousand, eight hundred seventeen".