668895 has 16 divisors (see below), whose sum is σ = 1127040. Its totient is φ = 337824.

The previous prime is 668879. The next prime is 668903. The reversal of 668895 is 598866.

It is not a de Polignac number, because 668895 - 2⁴ = 668879 is a prime.

668895 is a lucky number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 889 + ... + 1458.

It is an arithmetic number, because the mean of its divisors is an integer number (70440).

2⁶⁶⁸⁸⁹⁵ is an apocalyptic number.

668895 is a deficient number, since it is larger than the sum of its proper divisors (458145).

668895 is a wasteful number, since it uses less digits than its factorization.

668895 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2374.

The product of its digits is 103680, while the sum is 42.

The square root of 668895 is about 817.8600124716. The cubic root of 668895 is about 87.4552696546.

The spelling of 668895 in words is "six hundred sixty-eight thousand, eight hundred ninety-five".