2556685 has 4 divisors (see below), whose sum is σ = 3068028. Its totient is φ = 2045344.

The previous prime is 2556683. The next prime is 2556689. The reversal of 2556685 is 5866552.

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 1435204 + 1121481 = 1198^2 + 1059^2 .

It is a cyclic number.

It is not a de Polignac number, because 2556685 - 2¹ = 2556683 is a prime.

It is a d-powerful number, because it can be written as 2¹⁶ + 5² + 5⁵ + 6 + 6³ + 8⁷ + 5⁸ .

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2556683) 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, 255664 + ... + 255673.

It is an arithmetic number, because the mean of its divisors is an integer number (767007).

2^2556685 is an apocalyptic number.

It is an amenable number.

2556685 is a deficient number, since it is larger than the sum of its proper divisors (511343).

2556685 is an equidigital number, since it uses as much as digits as its factorization.

2556685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 511342.

The product of its digits is 72000, while the sum is 37.

The square root of 2556685 is about 1598.9637269182. The cubic root of 2556685 is about 136.7390026215.

It can be divided in two parts, 25566 and 85, that added together give a triangular number (25651 = T₂₂₆).

The spelling of 2556685 in words is "two million, five hundred fifty-six thousand, six hundred eighty-five".