2645581 has 2 divisors, whose sum is σ = 2645582. Its totient is φ = 2645580.

The previous prime is 2645569. The next prime is 2645597. The reversal of 2645581 is 1855462.

2645581 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2223081 + 422500 = 1491^2 + 650^2 .

It is a cyclic number.

It is not a de Polignac number, because 2645581 - 2⁵ = 2645549 is a prime.

It is a super-2 number, since 2×2645581² = 13998197655122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2645521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1322790 + 1322791.

It is an arithmetic number, because the mean of its divisors is an integer number (1322791).

2^2645581 is an apocalyptic number.

It is an amenable number.

2645581 is a deficient number, since it is larger than the sum of its proper divisors (1).

2645581 is an equidigital number, since it uses as much as digits as its factorization.

2645581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9600, while the sum is 31.

The square root of 2645581 is about 1626.5242082428. The cubic root of 2645581 is about 138.3057876477.

The spelling of 2645581 in words is "two million, six hundred forty-five thousand, five hundred eighty-one".