668301997 has 6 divisors (see below), whose sum is σ = 734580014. Its totient is φ = 607547160.

The previous prime is 668301983. The next prime is 668302003. The reversal of 668301997 is 799103866.

It can be written as a sum of positive squares in only one way, i.e., 496665796 + 171636201 = 22286^2 + 13101^2 .

It is a de Polignac number, because none of the positive numbers 2^k-668301997 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 668301997.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668301797) by changing a digit.

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, 2761458 + ... + 2761699.

Almost surely, 2^668301997 is an apocalyptic number.

It is an amenable number.

668301997 is a deficient number, since it is larger than the sum of its proper divisors (66278017).

668301997 is a wasteful number, since it uses less digits than its factorization.

668301997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5523179 (or 5523168 counting only the distinct ones).

The product of its (nonzero) digits is 489888, while the sum is 49.

The square root of 668301997 is about 25851.5376138442. The cubic root of 668301997 is about 874.2941777920.

The spelling of 668301997 in words is "six hundred sixty-eight million, three hundred one thousand, nine hundred ninety-seven".