18136985690 has 8 divisors (see below), whose sum is σ = 32646574260. Its totient is φ = 7254794272.

The previous prime is 18136985677. The next prime is 18136985717. The reversal of 18136985690 is 9658963181.

It can be written as a sum of positive squares in 2 ways, for example, as 17978250889 + 158734801 = 134083^2 + 12599^2 .

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

It is a super-2 number, since 2×18136985690² (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 3 ways as a sum of consecutive naturals, for example, 906849275 + ... + 906849294.

Almost surely, 2^18136985690 is an apocalyptic number.

18136985690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18136985690 is a deficient number, since it is larger than the sum of its proper divisors (14509588570).

18136985690 is a wasteful number, since it uses less digits than its factorization.

18136985690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1813698576.

The product of its (nonzero) digits is 2799360, while the sum is 56.

The spelling of 18136985690 in words is "eighteen billion, one hundred thirty-six million, nine hundred eighty-five thousand, six hundred ninety".