12815217 has 12 divisors (see below), whose sum is σ = 18676164. Its totient is φ = 8467200.

The previous prime is 12815207. The next prime is 12815221. The reversal of 12815217 is 71251821.

12815217 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 1766241 + 11048976 = 1329^2 + 3324^2 .

It is not a de Polignac number, because 12815217 - 2¹¹ = 12813169 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12815207) 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, 5284 + ... + 7317.

It is an arithmetic number, because the mean of its divisors is an integer number (1556347).

Almost surely, 2^12815217 is an apocalyptic number.

It is an amenable number.

12815217 is a deficient number, since it is larger than the sum of its proper divisors (5860947).

12815217 is a wasteful number, since it uses less digits than its factorization.

12815217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12720 (or 12717 counting only the distinct ones).

The product of its digits is 1120, while the sum is 27.

The square root of 12815217 is about 3579.8347727235. The cubic root of 12815217 is about 234.0140798015.

The spelling of 12815217 in words is "twelve million, eight hundred fifteen thousand, two hundred seventeen".