4545 has 12 divisors (see below), whose sum is σ = 7956. Its totient is φ = 2400.

The previous prime is 4523. The next prime is 4547. The reversal of 4545 is 5454.

It is a happy number.

4545 is nontrivially palindromic in base 8.

4545 is an esthetic number in base 10, because in such base its adjacent digits differ by 1.

It can be written as a sum of positive squares in 2 ways, for example, as 3249 + 1296 = 57^2 + 36^2 .

It is not a de Polignac number, because 4545 - 2⁵ = 4513 is a prime.

It is an alternating number because its digits alternate between even and odd.

4545 is an undulating number in base 10.

It is a Curzon number.

It is a nialpdrome in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4547) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6 + ... + 95.

It is an arithmetic number, because the mean of its divisors is an integer number (663).

2⁴⁵⁴⁵ is an apocalyptic number.

4545 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

It is an amenable number.

4545 is a deficient number, since it is larger than the sum of its proper divisors (3411).

4545 is a wasteful number, since it uses less digits than its factorization.

4545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112 (or 109 counting only the distinct ones).

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

The square root of 4545 is about 67.4166151627. The cubic root of 4545 is about 16.5644859373.

Multiplying 4545 by its sum of digits (18), we get a triangular number (81810 = T₄₀₄).

Adding to 4545 its reverse (5454), we get a palindrome (9999).

Subtracting 4545 from its reverse (5454), we obtain a palindrome (909).

The spelling of 4545 in words is "four thousand, five hundred forty-five".