2855581 has 2 divisors, whose sum is σ = 2855582. Its totient is φ = 2855580.

The previous prime is 2855557. The next prime is 2855591. The reversal of 2855581 is 1855582.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2452356 + 403225 = 1566^2 + 635^2 .

It is a cyclic number.

It is not a de Polignac number, because 2855581 - 2¹¹ = 2853533 is a prime.

It is a super-2 number, since 2×2855581² = 16308685695122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2855591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1427790 + 1427791.

It is an arithmetic number, because the mean of its divisors is an integer number (1427791).

2^2855581 is an apocalyptic number.

It is an amenable number.

2855581 is a deficient number, since it is larger than the sum of its proper divisors (1).

2855581 is an equidigital number, since it uses as much as digits as its factorization.

2855581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16000, while the sum is 34.

The square root of 2855581 is about 1689.8464427279. The cubic root of 2855581 is about 141.8724802414.

Subtracting from 2855581 its reverse (1855582), we obtain a palindrome (999999).

The spelling of 2855581 in words is "two million, eight hundred fifty-five thousand, five hundred eighty-one".