2543581 has 4 divisors (see below), whose sum is σ = 2625664. Its totient is φ = 2461500.

The previous prime is 2543573. The next prime is 2543609. The reversal of 2543581 is 1853452.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2543581 - 2³ = 2543573 is a prime.

It is a super-2 number, since 2×2543581² = 12939608607122, 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 (2543551) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40995 + ... + 41056.

It is an arithmetic number, because the mean of its divisors is an integer number (656416).

2^2543581 is an apocalyptic number.

It is an amenable number.

2543581 is a deficient number, since it is larger than the sum of its proper divisors (82083).

2543581 is an equidigital number, since it uses as much as digits as its factorization.

2543581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82082.

The product of its digits is 4800, while the sum is 28.

The square root of 2543581 is about 1594.8608089736. The cubic root of 2543581 is about 136.5049889270.

The spelling of 2543581 in words is "two million, five hundred forty-three thousand, five hundred eighty-one".