668606425 has 6 divisors (see below), whose sum is σ = 829071998. Its totient is φ = 534885120.

The previous prime is 668606401. The next prime is 668606453. The reversal of 668606425 is 524606866.

It can be written as a sum of positive squares in 3 ways, for example, as 1882384 + 666724041 = 1372^2 + 25821^2 .

It is not a de Polignac number, because 668606425 - 2⁹ = 668605913 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 13372104 + ... + 13372153.

Almost surely, 2^668606425 is an apocalyptic number.

It is an amenable number.

668606425 is a deficient number, since it is larger than the sum of its proper divisors (160465573).

668606425 is a wasteful number, since it uses less digits than its factorization.

668606425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26744267 (or 26744262 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 43.

The square root of 668606425 is about 25857.4249491321. The cubic root of 668606425 is about 874.4269118081.

The spelling of 668606425 in words is "six hundred sixty-eight million, six hundred six thousand, four hundred twenty-five".