668543 has 2 divisors, whose sum is σ = 668544. Its totient is φ = 668542.

The previous prime is 668539. The next prime is 668567. The reversal of 668543 is 345866.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 668543 - 2² = 668539 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (668513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334271 + 334272.

It is an arithmetic number, because the mean of its divisors is an integer number (334272).

2⁶⁶⁸⁵⁴³ is an apocalyptic number.

668543 is a deficient number, since it is larger than the sum of its proper divisors (1).

668543 is an equidigital number, since it uses as much as digits as its factorization.

668543 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17280, while the sum is 32.

The square root of 668543 is about 817.6447884014. The cubic root of 668543 is about 87.4399261121.

The spelling of 668543 in words is "six hundred sixty-eight thousand, five hundred forty-three".