668799 has 6 divisors (see below), whose sum is σ = 966056. Its totient is φ = 445860.

The previous prime is 668791. The next prime is 668803. The reversal of 668799 is 997866.

It is not a de Polignac number, because 668799 - 2³ = 668791 is a prime.

It is a Duffinian number.

668799 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668791) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 37147 + ... + 37164.

2⁶⁶⁸⁷⁹⁹ is an apocalyptic number.

668799 is a deficient number, since it is larger than the sum of its proper divisors (297257).

668799 is a wasteful number, since it uses less digits than its factorization.

668799 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74317 (or 74314 counting only the distinct ones).

The product of its digits is 163296, while the sum is 45.

The square root of 668799 is about 817.8013206152. The cubic root of 668799 is about 87.4510855860.

It can be divided in two parts, 6687 and 99, that added together give a triangular number (6786 = T₁₁₆).

The spelling of 668799 in words is "six hundred sixty-eight thousand, seven hundred ninety-nine".