12840257 has 16 divisors (see below), whose sum is σ = 14152320. Its totient is φ = 11606400.

The previous prime is 12840241. The next prime is 12840281. The reversal of 12840257 is 75204821.

12840257 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 12840257 - 2⁴ = 12840241 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12846257) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 41132 + ... + 41442.

It is an arithmetic number, because the mean of its divisors is an integer number (884520).

Almost surely, 2^12840257 is an apocalyptic number.

It is an amenable number.

12840257 is a deficient number, since it is larger than the sum of its proper divisors (1312063).

12840257 is a wasteful number, since it uses less digits than its factorization.

12840257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 424.

The product of its (nonzero) digits is 4480, while the sum is 29.

The square root of 12840257 is about 3583.3304341074. The cubic root of 12840257 is about 234.1663961249.

The spelling of 12840257 in words is "twelve million, eight hundred forty thousand, two hundred fifty-seven".