666387593 has 2 divisors, whose sum is σ = 666387594. Its totient is φ = 666387592.

The previous prime is 666387587. The next prime is 666387643. The reversal of 666387593 is 395783666.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 391723264 + 274664329 = 19792^2 + 16573^2 .

It is a cyclic number.

It is not a de Polignac number, because 666387593 - 2⁴ = 666387577 is a prime.

It is not a weakly prime, because it can be changed into another prime (666387583) 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, 333193796 + 333193797.

It is an arithmetic number, because the mean of its divisors is an integer number (333193797).

Almost surely, 2^666387593 is an apocalyptic number.

It is an amenable number.

666387593 is a deficient number, since it is larger than the sum of its proper divisors (1).

666387593 is an equidigital number, since it uses as much as digits as its factorization.

666387593 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4898880, while the sum is 53.

The square root of 666387593 is about 25814.4841707132. The cubic root of 666387593 is about 873.4585510716.

The spelling of 666387593 in words is "six hundred sixty-six million, three hundred eighty-seven thousand, five hundred ninety-three".