666844271 has 2 divisors, whose sum is σ = 666844272. Its totient is φ = 666844270.

The previous prime is 666844219. The next prime is 666844307. The reversal of 666844271 is 172448666.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 666844271 - 2⁶ = 666844207 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666844571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333422135 + 333422136.

It is an arithmetic number, because the mean of its divisors is an integer number (333422136).

Almost surely, 2^666844271 is an apocalyptic number.

666844271 is a deficient number, since it is larger than the sum of its proper divisors (1).

666844271 is an equidigital number, since it uses as much as digits as its factorization.

666844271 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 387072, while the sum is 44.

The square root of 666844271 is about 25823.3280388102. The cubic root of 666844271 is about 873.6580336864.

The spelling of 666844271 in words is "six hundred sixty-six million, eight hundred forty-four thousand, two hundred seventy-one".