135997540 has 72 divisors (see below), whose sum is σ = 336950712. Its totient is φ = 45964800.

The previous prime is 135997517. The next prime is 135997541. The reversal of 135997540 is 45799531.

It can be written as a sum of positive squares in 4 ways, for example, as 1623076 + 134374464 = 1274^2 + 11592^2 .

It is not an unprimeable number, because it can be changed into a prime (135997541) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 70590 + ... + 72490.

It is an arithmetic number, because the mean of its divisors is an integer number (4679871).

Almost surely, 2^135997540 is an apocalyptic number.

135997540 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 135997540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (168475356).

135997540 is an abundant number, since it is smaller than the sum of its proper divisors (200953172).

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

135997540 is a wasteful number, since it uses less digits than its factorization.

135997540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1997 (or 1988 counting only the distinct ones).

The product of its (nonzero) digits is 170100, while the sum is 43.

The square root of 135997540 is about 11661.7983175838. The cubic root of 135997540 is about 514.2532174499.

The spelling of 135997540 in words is "one hundred thirty-five million, nine hundred ninety-seven thousand, five hundred forty".