6446666 has 4 divisors (see below), whose sum is σ = 9670002. Its totient is φ = 3223332.

The previous prime is 6446659. The next prime is 6446669. The reversal of 6446666 is 6666446.

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

It can be written as a sum of positive squares in only one way, i.e., 6175225 + 271441 = 2485^2 + 521^2 .

6446666 is a modest number, since divided by 6666 gives 644 as remainder.

It is not an unprimeable number, because it can be changed into a prime (6446669) 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, 1611665 + ... + 1611668.

Almost surely, 2^6446666 is an apocalyptic number.

6446666 is a deficient number, since it is larger than the sum of its proper divisors (3223336).

6446666 is a wasteful number, since it uses less digits than its factorization.

6446666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3223335.

The product of its digits is 124416, while the sum is 38.

The square root of 6446666 is about 2539.0285543885. The cubic root of 6446666 is about 186.1137201057.

The spelling of 6446666 in words is "six million, four hundred forty-six thousand, six hundred sixty-six".