2556563 has 4 divisors (see below), whose sum is σ = 2581488. Its totient is φ = 2531640.

The previous prime is 2556559. The next prime is 2556569. The reversal of 2556563 is 3656552.

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

It is a cyclic number.

It is not a de Polignac number, because 2556563 - 2² = 2556559 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a plaindrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (2556569) 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, 12308 + ... + 12513.

It is an arithmetic number, because the mean of its divisors is an integer number (645372).

2^2556563 is an apocalyptic number.

2556563 is a deficient number, since it is larger than the sum of its proper divisors (24925).

2556563 is a wasteful number, since it uses less digits than its factorization.

2556563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24924.

The product of its digits is 27000, while the sum is 32.

The square root of 2556563 is about 1598.9255767546. The cubic root of 2556563 is about 136.7368276145.

The spelling of 2556563 in words is "two million, five hundred fifty-six thousand, five hundred sixty-three".