666451271 has 2 divisors, whose sum is σ = 666451272. Its totient is φ = 666451270.

The previous prime is 666451229. The next prime is 666451321. The reversal of 666451271 is 172154666.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 666451271 - 2¹⁴ = 666434887 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 (666451171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333225635 + 333225636.

It is an arithmetic number, because the mean of its divisors is an integer number (333225636).

Almost surely, 2^666451271 is an apocalyptic number.

666451271 is a deficient number, since it is larger than the sum of its proper divisors (1).

666451271 is an equidigital number, since it uses as much as digits as its factorization.

666451271 is an evil number, because the sum of its binary digits is even.

The product of its digits is 60480, while the sum is 38.

The square root of 666451271 is about 25815.7175185971. The cubic root of 666451271 is about 873.4863718787.

The spelling of 666451271 in words is "six hundred sixty-six million, four hundred fifty-one thousand, two hundred seventy-one".