668395 has 24 divisors (see below), whose sum is σ = 1001376. Its totient is φ = 419328.

The previous prime is 668347. The next prime is 668407. The reversal of 668395 is 593866.

668395 = 306² + 307² + ... + 312².

It is not a de Polignac number, because 668395 - 2⁹ = 667883 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 (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5859 + ... + 5971.

It is an arithmetic number, because the mean of its divisors is an integer number (41724).

2⁶⁶⁸³⁹⁵ is an apocalyptic number.

668395 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

668395 is a deficient number, since it is larger than the sum of its proper divisors (332981).

668395 is a wasteful number, since it uses less digits than its factorization.

668395 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151 (or 138 counting only the distinct ones).

The product of its digits is 38880, while the sum is 37.

The square root of 668395 is about 817.5542795436. The cubic root of 668395 is about 87.4334732417.

Subtracting from 668395 its reverse (593866), we obtain a square (74529 = 273²).

The spelling of 668395 in words is "six hundred sixty-eight thousand, three hundred ninety-five".