668142073 has 2 divisors, whose sum is σ = 668142074. Its totient is φ = 668142072.

The previous prime is 668142061. The next prime is 668142091. The reversal of 668142073 is 370241866.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 538796944 + 129345129 = 23212^2 + 11373^2 .

It is a cyclic number.

It is not a de Polignac number, because 668142073 - 2⁹ = 668141561 is a prime.

It is not a weakly prime, because it can be changed into another prime (668142043) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334071036 + 334071037.

It is an arithmetic number, because the mean of its divisors is an integer number (334071037).

Almost surely, 2^668142073 is an apocalyptic number.

It is an amenable number.

668142073 is a deficient number, since it is larger than the sum of its proper divisors (1).

668142073 is an equidigital number, since it uses as much as digits as its factorization.

668142073 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48384, while the sum is 37.

The square root of 668142073 is about 25848.4443052188. Note that the first 3 decimals coincide. The cubic root of 668142073 is about 874.2244329874.

The spelling of 668142073 in words is "six hundred sixty-eight million, one hundred forty-two thousand, seventy-three".