663642906 has 96 divisors (see below), whose sum is σ = 1510954560. Its totient is φ = 193577472.

The previous prime is 663642883. The next prime is 663642913. The reversal of 663642906 is 609246366.

663642906 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2466940 + ... + 2467208.

It is an arithmetic number, because the mean of its divisors is an integer number (15739110).

Almost surely, 2^663642906 is an apocalyptic number.

663642906 is an abundant number, since it is smaller than the sum of its proper divisors (847311654).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

663642906 is a wasteful number, since it uses less digits than its factorization.

663642906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 396 (or 377 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 42.

The square root of 663642906 is about 25761.2675542179. The cubic root of 663642906 is about 872.2577137506.

The spelling of 663642906 in words is "six hundred sixty-three million, six hundred forty-two thousand, nine hundred six".