6642399 has 8 divisors (see below), whose sum is σ = 8968960. Its totient is φ = 4372056.

The previous prime is 6642379. The next prime is 6642403. The reversal of 6642399 is 9932466.

It is a happy number.

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

It is not a de Polignac number, because 6642399 - 2⁸ = 6642143 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 (6642319) 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, 13777 + ... + 14250.

It is an arithmetic number, because the mean of its divisors is an integer number (1121120).

Almost surely, 2^6642399 is an apocalyptic number.

6642399 is a deficient number, since it is larger than the sum of its proper divisors (2326561).

6642399 is a wasteful number, since it uses less digits than its factorization.

6642399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28109.

The product of its digits is 69984, while the sum is 39.

The square root of 6642399 is about 2577.2851995850. The cubic root of 6642399 is about 187.9785606305.

The spelling of 6642399 in words is "six million, six hundred forty-two thousand, three hundred ninety-nine".