13503440 has 40 divisors (see below), whose sum is σ = 33245640. Its totient is φ = 5083136.

The previous prime is 13503437. The next prime is 13503449. The reversal of 13503440 is 4430531.

It can be written as a sum of positive squares in 4 ways, for example, as 1281424 + 12222016 = 1132^2 + 3496^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13503449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3605 + ... + 6324.

It is an arithmetic number, because the mean of its divisors is an integer number (831141).

Almost surely, 2^13503440 is an apocalyptic number.

13503440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

13503440 is an abundant number, since it is smaller than the sum of its proper divisors (19742200).

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

13503440 is a wasteful number, since it uses less digits than its factorization.

13503440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9959 (or 9953 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 20.

The square root of 13503440 is about 3674.7027090637. The cubic root of 13503440 is about 238.1303807429.

Adding to 13503440 its reverse (4430531), we get a palindrome (17933971).

The spelling of 13503440 in words is "thirteen million, five hundred three thousand, four hundred forty".