664947906 has 16 divisors (see below), whose sum is σ = 1519881024. Its totient is φ = 189985104.

The previous prime is 664947893. The next prime is 664947919. The reversal of 664947906 is 609749466.

It is an interprime number because it is at equal distance from previous prime (664947893) and next prime (664947919).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7916005 + ... + 7916088.

It is an arithmetic number, because the mean of its divisors is an integer number (94992564).

Almost surely, 2^664947906 is an apocalyptic number.

664947906 is an abundant number, since it is smaller than the sum of its proper divisors (854933118).

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

664947906 is a wasteful number, since it uses less digits than its factorization.

664947906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15832105.

The product of its (nonzero) digits is 1959552, while the sum is 51.

The square root of 664947906 is about 25786.5838373368. The cubic root of 664947906 is about 872.8290807703.

The spelling of 664947906 in words is "six hundred sixty-four million, nine hundred forty-seven thousand, nine hundred six".