2556791 has 2 divisors, whose sum is σ = 2556792. Its totient is φ = 2556790.

The previous prime is 2556761. The next prime is 2556793. The reversal of 2556791 is 1976552.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2556791 - 2¹⁰ = 2555767 is a prime.

Together with 2556793, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2556793) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1278395 + 1278396.

It is an arithmetic number, because the mean of its divisors is an integer number (1278396).

2^2556791 is an apocalyptic number.

2556791 is a deficient number, since it is larger than the sum of its proper divisors (1).

2556791 is an equidigital number, since it uses as much as digits as its factorization.

2556791 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18900, while the sum is 35.

The square root of 2556791 is about 1598.9968730426. The cubic root of 2556791 is about 136.7408923256.

The spelling of 2556791 in words is "two million, five hundred fifty-six thousand, seven hundred ninety-one".