18618313865 has 8 divisors (see below), whose sum is σ = 22369598280. Its totient is φ = 14876236672.

The previous prime is 18618313843. The next prime is 18618313951. The reversal of 18618313865 is 56831381681.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 10087390096 + 8530923769 = 100436^2 + 92363^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18618313865 is a prime.

It is a super-2 number, since 2×18618313865² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2297354 + ... + 2305443.

It is an arithmetic number, because the mean of its divisors is an integer number (2796199785).

Almost surely, 2^18618313865 is an apocalyptic number.

It is an amenable number.

18618313865 is a deficient number, since it is larger than the sum of its proper divisors (3751284415).

18618313865 is an equidigital number, since it uses as much as digits as its factorization.

18618313865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4603611.

The product of its digits is 829440, while the sum is 50.

The spelling of 18618313865 in words is "eighteen billion, six hundred eighteen million, three hundred thirteen thousand, eight hundred sixty-five".