18198885645 has 48 divisors (see below), whose sum is σ = 33462806832. Its totient is φ = 9118033920.

The previous prime is 18198885623. The next prime is 18198885667. The reversal of 18198885645 is 54658889181.

It is an interprime number because it is at equal distance from previous prime (18198885623) and next prime (18198885667).

It can be written as a sum of positive squares in 8 ways, for example, as 4652649 + 18194232996 = 2157^2 + 134886^2 .

It is not a de Polignac number, because 18198885645 - 2⁵ = 18198885613 is a prime.

It is a super-3 number, since 3×18198885645³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 391879 + ... + 435851.

It is an arithmetic number, because the mean of its divisors is an integer number (697141809).

Almost surely, 2^18198885645 is an apocalyptic number.

18198885645 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18198885645 is a deficient number, since it is larger than the sum of its proper divisors (15263921187).

18198885645 is a wasteful number, since it uses less digits than its factorization.

18198885645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44542 (or 44539 counting only the distinct ones).

The product of its digits is 22118400, while the sum is 63.

The spelling of 18198885645 in words is "eighteen billion, one hundred ninety-eight million, eight hundred eighty-five thousand, six hundred forty-five".