668769 has 8 divisors (see below), whose sum is σ = 922560. Its totient is φ = 430416.

The previous prime is 668761. The next prime is 668791. The reversal of 668769 is 967866.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 668769 - 2³ = 668761 is a prime.

It is a super-2 number, since 2×668769² = 894503950722, which contains 22 as substring.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 668769.

It is not an unprimeable number, because it can be changed into a prime (668761) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3757 + ... + 3930.

It is an arithmetic number, because the mean of its divisors is an integer number (115320).

2⁶⁶⁸⁷⁶⁹ is an apocalyptic number.

It is an amenable number.

668769 is a deficient number, since it is larger than the sum of its proper divisors (253791).

668769 is a wasteful number, since it uses less digits than its factorization.

668769 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7719.

The product of its digits is 108864, while the sum is 42.

The square root of 668769 is about 817.7829785463. The cubic root of 668769 is about 87.4497779825.

The spelling of 668769 in words is "six hundred sixty-eight thousand, seven hundred sixty-nine".