6643191 has 8 divisors (see below), whose sum is σ = 8944000. Its totient is φ = 4385592.

The previous prime is 6643181. The next prime is 6643201. The reversal of 6643191 is 1913466.

It is an interprime number because it is at equal distance from previous prime (6643181) and next prime (6643201).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 6643191 - 2⁶ = 6643127 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 (6643111) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10441 + ... + 11058.

It is an arithmetic number, because the mean of its divisors is an integer number (1118000).

Almost surely, 2^6643191 is an apocalyptic number.

6643191 is a deficient number, since it is larger than the sum of its proper divisors (2300809).

6643191 is a wasteful number, since it uses less digits than its factorization.

6643191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21605.

The product of its digits is 3888, while the sum is 30.

The square root of 6643191 is about 2577.4388450553. The cubic root of 6643191 is about 187.9860314806.

The spelling of 6643191 in words is "six million, six hundred forty-three thousand, one hundred ninety-one".