668719 has 2 divisors, whose sum is σ = 668720. Its totient is φ = 668718.

The previous prime is 668713. The next prime is 668737. The reversal of 668719 is 917866.

668719 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 668719 - 2⁵ = 668687 is a prime.

It is a super-2 number, since 2×668719² = 894370201922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (668713) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334359 + 334360.

It is an arithmetic number, because the mean of its divisors is an integer number (334360).

2⁶⁶⁸⁷¹⁹ is an apocalyptic number.

668719 is a deficient number, since it is larger than the sum of its proper divisors (1).

668719 is an equidigital number, since it uses as much as digits as its factorization.

668719 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18144, while the sum is 37.

The square root of 668719 is about 817.7524075171. The cubic root of 668719 is about 87.4475985564.

The spelling of 668719 in words is "six hundred sixty-eight thousand, seven hundred nineteen".