13521387 has 18 divisors (see below), whose sum is σ = 19919676. Its totient is φ = 8152320.

The previous prime is 13521373. The next prime is 13521397. The reversal of 13521387 is 78312531.

It is not a de Polignac number, because 13521387 - 2⁶ = 13521323 is a prime.

It is not an unprimeable number, because it can be changed into a prime (13521367) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 69963 + ... + 70155.

Almost surely, 2^13521387 is an apocalyptic number.

13521387 is a deficient number, since it is larger than the sum of its proper divisors (6398289).

13521387 is an equidigital number, since it uses as much as digits as its factorization.

13521387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 411 (or 207 counting only the distinct ones).

The product of its digits is 5040, while the sum is 30.

The square root of 13521387 is about 3677.1438644687. The cubic root of 13521387 is about 238.2358312548.

The spelling of 13521387 in words is "thirteen million, five hundred twenty-one thousand, three hundred eighty-seven".