2641581 has 18 divisors (see below), whose sum is σ = 3963050. Its totient is φ = 1695456.

The previous prime is 2641577. The next prime is 2641631. The reversal of 2641581 is 1851462.

2641581 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 695556 + 1946025 = 834^2 + 1395^2 .

It is not a de Polignac number, because 2641581 - 2² = 2641577 is a prime.

It is a super-2 number, since 2×2641581² = 13955900359122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2641501) 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 in 17 ways as a sum of consecutive naturals, for example, 7395 + ... + 7743.

2^2641581 is an apocalyptic number.

It is an amenable number.

2641581 is a deficient number, since it is larger than the sum of its proper divisors (1321469).

2641581 is a wasteful number, since it uses less digits than its factorization.

2641581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 413 (or 381 counting only the distinct ones).

The product of its digits is 1920, while the sum is 27.

The square root of 2641581 is about 1625.2941272274. The cubic root of 2641581 is about 138.2360484359.

The spelling of 2641581 in words is "two million, six hundred forty-one thousand, five hundred eighty-one".