2556517 has 4 divisors (see below), whose sum is σ = 2561580. Its totient is φ = 2551456.

The previous prime is 2556509. The next prime is 2556523. The reversal of 2556517 is 7156552.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1726596 + 829921 = 1314^2 + 911^2 .

It is a cyclic number.

It is not a de Polignac number, because 2556517 - 2³ = 2556509 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 (2556577) 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, 1678 + ... + 2815.

It is an arithmetic number, because the mean of its divisors is an integer number (640395).

2^2556517 is an apocalyptic number.

It is an amenable number.

2556517 is a deficient number, since it is larger than the sum of its proper divisors (5063).

2556517 is an equidigital number, since it uses as much as digits as its factorization.

2556517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5062.

The product of its digits is 10500, while the sum is 31.

The square root of 2556517 is about 1598.9111920304. The cubic root of 2556517 is about 136.7360075119.

The spelling of 2556517 in words is "two million, five hundred fifty-six thousand, five hundred seventeen".