13521247 has 4 divisors (see below), whose sum is σ = 13536880. Its totient is φ = 13505616.

The previous prime is 13521197. The next prime is 13521253. The reversal of 13521247 is 74212531.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 74212531 = 17 ⋅4365443.

It is a cyclic number.

It is not a de Polignac number, because 13521247 - 2¹⁵ = 13488479 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13522247) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6438 + ... + 8275.

It is an arithmetic number, because the mean of its divisors is an integer number (3384220).

Almost surely, 2^13521247 is an apocalyptic number.

13521247 is a deficient number, since it is larger than the sum of its proper divisors (15633).

13521247 is an equidigital number, since it uses as much as digits as its factorization.

13521247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15632.

The product of its digits is 1680, while the sum is 25.

The square root of 13521247 is about 3677.1248279056. The cubic root of 13521247 is about 238.2350090233.

Adding to 13521247 its reverse (74212531), we get a palindrome (87733778).

The spelling of 13521247 in words is "thirteen million, five hundred twenty-one thousand, two hundred forty-seven".