45540 has 72 divisors (see below), whose sum is σ = 157248. Its totient is φ = 10560.

The previous prime is 45533. The next prime is 45541. The reversal of 45540 is 4554.

45540 = T₁₁ + T₁₂ + ... + T₆₄.

45540 = 33² + 34² + ... + 55².

It is a happy number.

45540 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a super-3 number, since 3×45540³ = 283335070392000, which contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an Ulam number.

It is a nialpdrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (45541) by changing a digit.

45540 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1969 + ... + 1991.

It is an arithmetic number, because the mean of its divisors is an integer number (2184).

2⁴⁵⁵⁴⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 45540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (78624).

45540 is an abundant number, since it is smaller than the sum of its proper divisors (111708).

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

45540 is a wasteful number, since it uses less digits than its factorization.

45540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49 (or 44 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 18.

The square root of 45540 is about 213.4010309253. The cubic root of 45540 is about 35.7106434381.

It can be divided in two parts, 45 and 540, that added together give a palindrome (585).

The spelling of 45540 in words is "forty-five thousand, five hundred forty".