668319693 has 4 divisors (see below), whose sum is σ = 891092928. Its totient is φ = 445546460.

The previous prime is 668319689. The next prime is 668319709. The reversal of 668319693 is 396913866.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 668319693 - 2² = 668319689 is a prime.

It is a super-2 number, since 2×668319693² = 893302424103228498, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668319643) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111386613 + ... + 111386618.

It is an arithmetic number, because the mean of its divisors is an integer number (222773232).

Almost surely, 2^668319693 is an apocalyptic number.

It is an amenable number.

668319693 is a deficient number, since it is larger than the sum of its proper divisors (222773235).

668319693 is a wasteful number, since it uses less digits than its factorization.

668319693 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222773234.

The product of its digits is 1259712, while the sum is 51.

The square root of 668319693 is about 25851.8798736185. The cubic root of 668319693 is about 874.3018945495.

The spelling of 668319693 in words is "six hundred sixty-eight million, three hundred nineteen thousand, six hundred ninety-three".