13181440 has 80 divisors (see below), whose sum is σ = 33390720. Its totient is φ = 4976640.

The previous prime is 13181423. The next prime is 13181453. The reversal of 13181440 is 4418131.

It is a tau number, because it is divible by the number of its divisors (80).

It is a nialpdrome in base 8 and base 16.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48505 + ... + 48775.

It is an arithmetic number, because the mean of its divisors is an integer number (417384).

Almost surely, 2^13181440 is an apocalyptic number.

13181440 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 13181440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16695360).

13181440 is an abundant number, since it is smaller than the sum of its proper divisors (20209280).

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

13181440 is an equidigital number, since it uses as much as digits as its factorization.

13181440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 313 (or 297 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 22.

The square root of 13181440 is about 3630.6252904975. The cubic root of 13181440 is about 236.2223318941. Note that the first 3 decimals are identical.

Adding to 13181440 its reverse (4418131), we get a palindrome (17599571).

The spelling of 13181440 in words is "thirteen million, one hundred eighty-one thousand, four hundred forty".