6642257 has 4 divisors (see below), whose sum is σ = 7032996. Its totient is φ = 6251520.

The previous prime is 6642211. The next prime is 6642281. The reversal of 6642257 is 7522466.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2835856 + 3806401 = 1684^2 + 1951^2 .

It is a cyclic number.

It is not a de Polignac number, because 6642257 - 2¹⁴ = 6625873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6602257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 195344 + ... + 195377.

It is an arithmetic number, because the mean of its divisors is an integer number (1758249).

Almost surely, 2^6642257 is an apocalyptic number.

It is an amenable number.

6642257 is a deficient number, since it is larger than the sum of its proper divisors (390739).

6642257 is a wasteful number, since it uses less digits than its factorization.

6642257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 390738.

The product of its digits is 20160, while the sum is 32.

The square root of 6642257 is about 2577.2576510702. The cubic root of 6642257 is about 187.9772210971.

The spelling of 6642257 in words is "six million, six hundred forty-two thousand, two hundred fifty-seven".