6661646 has 16 divisors (see below), whose sum is σ = 10378368. Its totient is φ = 3204600.

The previous prime is 6661643. The next prime is 6661649. The reversal of 6661646 is 6461666.

It is an interprime number because it is at equal distance from previous prime (6661643) and next prime (6661649).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6661643) 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, 5561 + ... + 6651.

It is an arithmetic number, because the mean of its divisors is an integer number (648648).

Almost surely, 2^6661646 is an apocalyptic number.

6661646 is a deficient number, since it is larger than the sum of its proper divisors (3716722).

6661646 is a wasteful number, since it uses less digits than its factorization.

6661646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1207.

The product of its digits is 31104, while the sum is 35.

The square root of 6661646 is about 2581.0164664333. The cubic root of 6661646 is about 188.1599476286.

The spelling of 6661646 in words is "six million, six hundred sixty-one thousand, six hundred forty-six".