6642791 has 4 divisors (see below), whose sum is σ = 6931632. Its totient is φ = 6353952.

The previous prime is 6642763. The next prime is 6642793. The reversal of 6642791 is 1972466.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 6642791 - 2¹⁴ = 6626407 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 (6642793) 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 3 ways as a sum of consecutive naturals, for example, 144386 + ... + 144431.

It is an arithmetic number, because the mean of its divisors is an integer number (1732908).

Almost surely, 2^6642791 is an apocalyptic number.

6642791 is a deficient number, since it is larger than the sum of its proper divisors (288841).

6642791 is a wasteful number, since it uses less digits than its factorization.

6642791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 288840.

The product of its digits is 18144, while the sum is 35.

The square root of 6642791 is about 2577.3612474777. The cubic root of 6642791 is about 187.9822583982.

The spelling of 6642791 in words is "six million, six hundred forty-two thousand, seven hundred ninety-one".