668994447 has 32 divisors (see below), whose sum is σ = 1013589504. Its totient is φ = 388886400.

The previous prime is 668994439. The next prime is 668994457. The reversal of 668994447 is 744499866.

668994447 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 668994447 - 2³ = 668994439 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668994457) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 82833 + ... + 90549.

It is an arithmetic number, because the mean of its divisors is an integer number (31674672).

Almost surely, 2^668994447 is an apocalyptic number.

668994447 is a deficient number, since it is larger than the sum of its proper divisors (344595057).

668994447 is a wasteful number, since it uses less digits than its factorization.

668994447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7839.

The product of its digits is 10450944, while the sum is 57.

The square root of 668994447 is about 25864.9269668406. The cubic root of 668994447 is about 874.5960353519.

The spelling of 668994447 in words is "six hundred sixty-eight million, nine hundred ninety-four thousand, four hundred forty-seven".