18181818365 has 8 divisors (see below), whose sum is σ = 22117061688. Its totient is φ = 14346201600.

The previous prime is 18181818301. The next prime is 18181818383. The reversal of 18181818365 is 56381818181.

It can be written as a sum of positive squares in 4 ways, for example, as 3292693924 + 14889124441 = 57382^2 + 122021^2 .

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

It is not a de Polignac number, because 18181818365 - 2⁶ = 18181818301 is a prime.

It is a super-3 number, since 3×18181818365³ (a number of 32 digits) contains 333 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

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, 24906236 + ... + 24906965.

It is an arithmetic number, because the mean of its divisors is an integer number (2764632711).

Almost surely, 2^18181818365 is an apocalyptic number.

It is an amenable number.

18181818365 is a deficient number, since it is larger than the sum of its proper divisors (3935243323).

18181818365 is an equidigital number, since it uses as much as digits as its factorization.

18181818365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49813279.

The product of its digits is 368640, while the sum is 50.

The spelling of 18181818365 in words is "eighteen billion, one hundred eighty-one million, eight hundred eighteen thousand, three hundred sixty-five".