2556217 has 2 divisors, whose sum is σ = 2556218. Its totient is φ = 2556216.

The previous prime is 2556193. The next prime is 2556233. The reversal of 2556217 is 7126552.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2399401 + 156816 = 1549^2 + 396^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2556217 is a prime.

It is not a weakly prime, because it can be changed into another prime (2556277) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1278108 + 1278109.

It is an arithmetic number, because the mean of its divisors is an integer number (1278109).

2^2556217 is an apocalyptic number.

It is an amenable number.

2556217 is a deficient number, since it is larger than the sum of its proper divisors (1).

2556217 is an equidigital number, since it uses as much as digits as its factorization.

2556217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4200, while the sum is 28.

The square root of 2556217 is about 1598.8173754372. The cubic root of 2556217 is about 136.7306587755.

The spelling of 2556217 in words is "two million, five hundred fifty-six thousand, two hundred seventeen".