6639197 has 6 divisors (see below), whose sum is σ = 7053018. Its totient is φ = 6248384.

The previous prime is 6639119. The next prime is 6639209. The reversal of 6639197 is 7919366.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 2910436 + 3728761 = 1706^2 + 1931^2 .

It is not a de Polignac number, because 6639197 - 2¹⁴ = 6622813 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 (6639107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11198 + ... + 11775.

It is an arithmetic number, because the mean of its divisors is an integer number (1175503).

Almost surely, 2^6639197 is an apocalyptic number.

It is an amenable number.

6639197 is a deficient number, since it is larger than the sum of its proper divisors (413821).

6639197 is a wasteful number, since it uses less digits than its factorization.

6639197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23007 (or 22990 counting only the distinct ones).

The product of its digits is 61236, while the sum is 41.

The square root of 6639197 is about 2576.6639284160. The cubic root of 6639197 is about 187.9483504562.

The spelling of 6639197 in words is "six million, six hundred thirty-nine thousand, one hundred ninety-seven".