6646406 has 16 divisors (see below), whose sum is σ = 10847088. Its totient is φ = 3036000.

The previous prime is 6646403. The next prime is 6646417. The reversal of 6646406 is 6046466.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6646403) 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 7 ways as a sum of consecutive naturals, for example, 1361 + ... + 3891.

It is an arithmetic number, because the mean of its divisors is an integer number (677943).

Almost surely, 2^6646406 is an apocalyptic number.

6646406 is a deficient number, since it is larger than the sum of its proper divisors (4200682).

6646406 is a wasteful number, since it uses less digits than its factorization.

6646406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2647.

The product of its (nonzero) digits is 20736, while the sum is 32.

The square root of 6646406 is about 2578.0624507564. The cubic root of 6646406 is about 188.0163521313.

The spelling of 6646406 in words is "six million, six hundred forty-six thousand, four hundred six".