13521540 has 96 divisors (see below), whose sum is σ = 41328000. Its totient is φ = 3290112.

The previous prime is 13521533. The next prime is 13521551. The reversal of 13521540 is 4512531.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 32856 + ... + 33264.

It is an arithmetic number, because the mean of its divisors is an integer number (430500).

Almost surely, 2^13521540 is an apocalyptic number.

13521540 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 13521540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20664000).

13521540 is an abundant number, since it is smaller than the sum of its proper divisors (27806460).

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

13521540 is a wasteful number, since it uses less digits than its factorization.

13521540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 469 (or 467 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 13521540 is about 3677.1646686000. The cubic root of 13521540 is about 238.2367298299.

Subtracting from 13521540 its reverse (4512531), we obtain a palindrome (9009009).

The spelling of 13521540 in words is "thirteen million, five hundred twenty-one thousand, five hundred forty".