135997187328 has 144 divisors (see below), whose sum is σ = 402386745600. Its totient is φ = 45307699200.

The previous prime is 135997187239. The next prime is 135997187387. The reversal of 135997187328 is 823781799531.

135997187328 is a `hidden beast` number, since 1 + 3 + 599 + 7 + 1 + 8 + 7 + 32 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-2 number, since 2×135997187328² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16245928 + ... + 16254296.

It is an arithmetic number, because the mean of its divisors is an integer number (2794352400).

Almost surely, 2^135997187328 is an apocalyptic number.

135997187328 is a gapful number since it is divisible by the number (18) 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 135997187328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (201193372800).

135997187328 is an abundant number, since it is smaller than the sum of its proper divisors (266389558272).

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

135997187328 is an equidigital number, since it uses as much as digits as its factorization.

135997187328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10745 (or 10725 counting only the distinct ones).

The product of its digits is 22861440, while the sum is 63.

The spelling of 135997187328 in words is "one hundred thirty-five billion, nine hundred ninety-seven million, one hundred eighty-seven thousand, three hundred twenty-eight".