18135691500 has 96 divisors (see below), whose sum is σ = 52862846400. Its totient is φ = 4831449600.

The previous prime is 18135691489. The next prime is 18135691507. The reversal of 18135691500 is 519653181.

It is not an unprimeable number, because it can be changed into a prime (18135691507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1688146 + ... + 1698854.

It is an arithmetic number, because the mean of its divisors is an integer number (550654650).

Almost surely, 2^18135691500 is an apocalyptic number.

18135691500 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18135691500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26431423200).

18135691500 is an abundant number, since it is smaller than the sum of its proper divisors (34727154900).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18135691500 is a wasteful number, since it uses less digits than its factorization.

18135691500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11860 (or 11848 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 39.

The spelling of 18135691500 in words is "eighteen billion, one hundred thirty-five million, six hundred ninety-one thousand, five hundred".