115540 has 24 divisors (see below), whose sum is σ = 249480. Its totient is φ = 44928.

The previous prime is 115523. The next prime is 115547. The reversal of 115540 is 45511.

Added to its reverse (45511) it gives a 5-th power (161051 = 11⁵).

It is a happy number.

115540 is nontrivially palindromic in base 11.

It can be written as a sum of positive squares in 4 ways, for example, as 30276 + 85264 = 174^2 + 292^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (115547) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1006 + ... + 1114.

It is an arithmetic number, because the mean of its divisors is an integer number (10395).

2¹¹⁵⁵⁴⁰ is an apocalyptic number.

115540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

115540 is an abundant number, since it is smaller than the sum of its proper divisors (133940).

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

115540 is a wasteful number, since it uses less digits than its factorization.

115540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171 (or 169 counting only the distinct ones).

The product of its (nonzero) digits is 100, while the sum is 16.

The square root of 115540 is about 339.9117532537. The cubic root of 115540 is about 48.7054381305.

Subtracting from 115540 its product of nonzero digits (100), we obtain a triangular number (115440 = T₄₈₀).

Adding to 115540 its reverse (45511), we get a 5-th power (161051 = 11⁵).

The spelling of 115540 in words is "one hundred fifteen thousand, five hundred forty".