2909581 has 2 divisors, whose sum is σ = 2909582. Its totient is φ = 2909580.

The previous prime is 2909573. The next prime is 2909587. The reversal of 2909581 is 1859092.

2909581 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1550025 + 1359556 = 1245^2 + 1166^2 .

It is a cyclic number.

It is not a de Polignac number, because 2909581 - 2³ = 2909573 is a prime.

It is a super-2 number, since 2×2909581² = 16931323191122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2909587) 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, 1454790 + 1454791.

It is an arithmetic number, because the mean of its divisors is an integer number (1454791).

2^2909581 is an apocalyptic number.

It is an amenable number.

2909581 is a deficient number, since it is larger than the sum of its proper divisors (1).

2909581 is an equidigital number, since it uses as much as digits as its factorization.

2909581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6480, while the sum is 34.

The square root of 2909581 is about 1705.7493954271. The cubic root of 2909581 is about 142.7611871334.

The spelling of 2909581 in words is "two million, nine hundred nine thousand, five hundred eighty-one".