6661849 has 2 divisors, whose sum is σ = 6661850. Its totient is φ = 6661848.

The previous prime is 6661783. The next prime is 6661873. The reversal of 6661849 is 9481666.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4579600 + 2082249 = 2140^2 + 1443^2 .

It is a cyclic number.

It is not a de Polignac number, because 6661849 - 2⁹ = 6661337 is a prime.

It is not a weakly prime, because it can be changed into another prime (6661049) 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 as a sum of consecutive naturals, namely, 3330924 + 3330925.

It is an arithmetic number, because the mean of its divisors is an integer number (3330925).

Almost surely, 2^6661849 is an apocalyptic number.

It is an amenable number.

6661849 is a deficient number, since it is larger than the sum of its proper divisors (1).

6661849 is an equidigital number, since it uses as much as digits as its factorization.

6661849 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 62208, while the sum is 40.

The square root of 6661849 is about 2581.0557917255. The cubic root of 6661849 is about 188.1618588721.

The spelling of 6661849 in words is "six million, six hundred sixty-one thousand, eight hundred forty-nine".