2556731 has 4 divisors (see below), whose sum is σ = 2565264. Its totient is φ = 2548200.

The previous prime is 2556713. The next prime is 2556739. The reversal of 2556731 is 1376552.

2556731 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2556731 is a prime.

It is a super-2 number, since 2×2556731² = 13073746812722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2556694 and 2556703.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2556739) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3800 + ... + 4421.

It is an arithmetic number, because the mean of its divisors is an integer number (641316).

2^2556731 is an apocalyptic number.

2556731 is a deficient number, since it is larger than the sum of its proper divisors (8533).

2556731 is an equidigital number, since it uses as much as digits as its factorization.

2556731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8532.

The product of its digits is 6300, while the sum is 29.

The square root of 2556731 is about 1598.9781111698. The cubic root of 2556731 is about 136.7398226882.

The spelling of 2556731 in words is "two million, five hundred fifty-six thousand, seven hundred thirty-one".