13251440 has 40 divisors (see below), whose sum is σ = 31256928. Its totient is φ = 5223680.

The previous prime is 13251437. The next prime is 13251451. The reversal of 13251440 is 4415231.

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 an unprimeable number.

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, 4514 + ... + 6846.

Almost surely, 2^13251440 is an apocalyptic number.

13251440 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 13251440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15628464).

13251440 is an abundant number, since it is smaller than the sum of its proper divisors (18005488).

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

13251440 is a wasteful number, since it uses less digits than its factorization.

13251440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2417 (or 2411 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 13251440 is about 3640.2527384785. The cubic root of 13251440 is about 236.6397465468.

Adding to 13251440 its reverse (4415231), we get a palindrome (17666671).

The spelling of 13251440 in words is "thirteen million, two hundred fifty-one thousand, four hundred forty".