13521240 has 144 divisors (see below), whose sum is σ = 46584720. Its totient is φ = 3400320.

The previous prime is 13521197. The next prime is 13521253. The reversal of 13521240 is 4212531.

It is a super-2 number, since 2×13521240² = 365647862275200, which contains 22 as substring.

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

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 35 ways as a sum of consecutive naturals, for example, 190405 + ... + 190475.

It is an arithmetic number, because the mean of its divisors is an integer number (323505).

Almost surely, 2^13521240 is an apocalyptic number.

13521240 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 13521240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23292360).

13521240 is an abundant number, since it is smaller than the sum of its proper divisors (33063480).

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

13521240 is a wasteful number, since it uses less digits than its factorization.

13521240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134 (or 104 counting only the distinct ones).

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

The square root of 13521240 is about 3677.1238760749. The cubic root of 13521240 is about 238.2349679115.

Adding to 13521240 its reverse (4212531), we get a palindrome (17733771).

The spelling of 13521240 in words is "thirteen million, five hundred twenty-one thousand, two hundred forty".