13501440 has 132 divisors (see below), whose sum is σ = 46941804. Its totient is φ = 3588096.

The previous prime is 13501427. The next prime is 13501447. The reversal of 13501440 is 4410531.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 9437184 + 4064256 = 3072^2 + 2016^2 .

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

It is not an unprimeable number, because it can be changed into a prime (13501447) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 45934 + ... + 46226.

Almost surely, 2^13501440 is an apocalyptic number.

13501440 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 13501440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23470902).

13501440 is an abundant number, since it is smaller than the sum of its proper divisors (33440364).

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

13501440 is a wasteful number, since it uses less digits than its factorization.

13501440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 324 (or 303 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 13501440 is about 3674.4305681289. The cubic root of 13501440 is about 238.1186236332.

Adding to 13501440 its reverse (4410531), we get a palindrome (17911971).

Subtracting from 13501440 its reverse (4410531), we obtain a palindrome (9090909).

The spelling of 13501440 in words is "thirteen million, five hundred one thousand, four hundred forty".