2555221 has 2 divisors, whose sum is σ = 2555222. Its totient is φ = 2555220.

The previous prime is 2555213. The next prime is 2555227. The reversal of 2555221 is 1225552.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1535121 + 1020100 = 1239^2 + 1010^2 .

It is a cyclic number.

It is not a de Polignac number, because 2555221 - 2³ = 2555213 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2555192 and 2555201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2555227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1277610 + 1277611.

It is an arithmetic number, because the mean of its divisors is an integer number (1277611).

2^2555221 is an apocalyptic number.

It is an amenable number.

2555221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2555221 is an equidigital number, since it uses as much as digits as its factorization.

2555221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1000, while the sum is 22.

The square root of 2555221 is about 1598.5058648626. The cubic root of 2555221 is about 136.7128979688.

It can be divided in two parts, 255 and 5221, that added together give a square (5476 = 74²).

The spelling of 2555221 in words is "two million, five hundred fifty-five thousand, two hundred twenty-one".