2255581 has 2 divisors, whose sum is σ = 2255582. Its totient is φ = 2255580.

The previous prime is 2255573. The next prime is 2255609. The reversal of 2255581 is 1855522.

It is an a-pointer prime, because the next prime (2255609) can be obtained adding 2255581 to its sum of digits (28).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2044900 + 210681 = 1430^2 + 459^2 .

It is a cyclic number.

It is not a de Polignac number, because 2255581 - 2³ = 2255573 is a prime.

It is a super-2 number, since 2×2255581² = 10175291295122, which contains 22 as substring.

It is equal to p₁₆₆₄₅₆ and since 2255581 and 166456 have the same sum of digits, it is a Honaker prime.

It is a plaindrome in base 16.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2255501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1127790 + 1127791.

It is an arithmetic number, because the mean of its divisors is an integer number (1127791).

2^2255581 is an apocalyptic number.

It is an amenable number.

2255581 is a deficient number, since it is larger than the sum of its proper divisors (1).

2255581 is an equidigital number, since it uses as much as digits as its factorization.

2255581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4000, while the sum is 28.

The square root of 2255581 is about 1501.8591811485. The cubic root of 2255581 is about 131.1453236443.

The spelling of 2255581 in words is "two million, two hundred fifty-five thousand, five hundred eighty-one".