6643579 has 4 divisors (see below), whose sum is σ = 6857920. Its totient is φ = 6429240.

The previous prime is 6643537. The next prime is 6643589. The reversal of 6643579 is 9753466.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9753466 = 2 ⋅4876733.

It is a cyclic number.

It is not a de Polignac number, because 6643579 - 2²¹ = 4546427 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6643589) 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, 107124 + ... + 107185.

It is an arithmetic number, because the mean of its divisors is an integer number (1714480).

Almost surely, 2^6643579 is an apocalyptic number.

6643579 is a deficient number, since it is larger than the sum of its proper divisors (214341).

6643579 is a wasteful number, since it uses less digits than its factorization.

6643579 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214340.

The product of its digits is 136080, while the sum is 40.

The square root of 6643579 is about 2577.5141124735. The cubic root of 6643579 is about 187.9896912259.

The spelling of 6643579 in words is "six million, six hundred forty-three thousand, five hundred seventy-nine".