6643406 has 32 divisors (see below), whose sum is σ = 12545280. Its totient is φ = 2563200.

The previous prime is 6643381. The next prime is 6643411. The reversal of 6643406 is 6043466.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27446 + ... + 27686.

It is an arithmetic number, because the mean of its divisors is an integer number (392040).

Almost surely, 2^6643406 is an apocalyptic number.

6643406 is a deficient number, since it is larger than the sum of its proper divisors (5901874).

6643406 is a wasteful number, since it uses less digits than its factorization.

6643406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 440.

The product of its (nonzero) digits is 10368, while the sum is 29.

The square root of 6643406 is about 2577.4805527879. The cubic root of 6643406 is about 187.9880594499.

The spelling of 6643406 in words is "six million, six hundred forty-three thousand, four hundred six".