6639143 has 4 divisors (see below), whose sum is σ = 7587600. Its totient is φ = 5690688.

The previous prime is 6639119. The next prime is 6639209. The reversal of 6639143 is 3419366.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 6639143 - 2¹⁸ = 6376999 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6639943) 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, 474218 + ... + 474231.

It is an arithmetic number, because the mean of its divisors is an integer number (1896900).

Almost surely, 2^6639143 is an apocalyptic number.

6639143 is a deficient number, since it is larger than the sum of its proper divisors (948457).

6639143 is an equidigital number, since it uses as much as digits as its factorization.

6639143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 948456.

The product of its digits is 11664, while the sum is 32.

The square root of 6639143 is about 2576.6534497289. The cubic root of 6639143 is about 187.9478408946.

The spelling of 6639143 in words is "six million, six hundred thirty-nine thousand, one hundred forty-three".