6646657 has 2 divisors, whose sum is σ = 6646658. Its totient is φ = 6646656.

The previous prime is 6646613. The next prime is 6646663. The reversal of 6646657 is 7566466.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3837681 + 2808976 = 1959^2 + 1676^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6646657 is a prime.

It is not a weakly prime, because it can be changed into another prime (6646687) 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 as a sum of consecutive naturals, namely, 3323328 + 3323329.

It is an arithmetic number, because the mean of its divisors is an integer number (3323329).

Almost surely, 2^6646657 is an apocalyptic number.

It is an amenable number.

6646657 is a deficient number, since it is larger than the sum of its proper divisors (1).

6646657 is an equidigital number, since it uses as much as digits as its factorization.

6646657 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 181440, while the sum is 40.

The square root of 6646657 is about 2578.1111302657. Note that the first 4 decimals coincide. The cubic root of 6646657 is about 188.0187188997.

The spelling of 6646657 in words is "six million, six hundred forty-six thousand, six hundred fifty-seven".