6442581 has 4 divisors (see below), whose sum is σ = 8590112. Its totient is φ = 4295052.

The previous prime is 6442573. The next prime is 6442591. The reversal of 6442581 is 1852446.

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 not a de Polignac number, because 6442581 - 2³ = 6442573 is a prime.

It is a super-2 number, since 2×6442581² = 83013699883122, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

6442581 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6442531) 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 3 ways as a sum of consecutive naturals, for example, 1073761 + ... + 1073766.

It is an arithmetic number, because the mean of its divisors is an integer number (2147528).

Almost surely, 2^6442581 is an apocalyptic number.

It is an amenable number.

6442581 is a deficient number, since it is larger than the sum of its proper divisors (2147531).

6442581 is a wasteful number, since it uses less digits than its factorization.

6442581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2147530.

The product of its digits is 7680, while the sum is 30.

The square root of 6442581 is about 2538.2239853882. The cubic root of 6442581 is about 186.0744008054.

The spelling of 6442581 in words is "six million, four hundred forty-two thousand, five hundred eighty-one".