6664191 has 8 divisors (see below), whose sum is σ = 8977584. Its totient is φ = 4396800.

The previous prime is 6664169. The next prime is 6664199. The reversal of 6664191 is 1914666.

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

It is not a de Polignac number, because 6664191 - 2⁵ = 6664159 is a prime.

It is a super-2 number, since 2×6664191² = 88822883368962, which contains 22 as substring.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6664199) 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, 11160 + ... + 11741.

It is an arithmetic number, because the mean of its divisors is an integer number (1122198).

Almost surely, 2^6664191 is an apocalyptic number.

6664191 is a deficient number, since it is larger than the sum of its proper divisors (2313393).

6664191 is a wasteful number, since it uses less digits than its factorization.

6664191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23001.

The product of its digits is 7776, while the sum is 33.

The square root of 6664191 is about 2581.5094421675. The cubic root of 6664191 is about 188.1839059766.

The spelling of 6664191 in words is "six million, six hundred sixty-four thousand, one hundred ninety-one".