666584251 has 2 divisors, whose sum is σ = 666584252. Its totient is φ = 666584250.

The previous prime is 666584209. The next prime is 666584257. The reversal of 666584251 is 152485666.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 666584251 - 2⁷ = 666584123 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 666584198 and 666584207.

It is not a weakly prime, because it can be changed into another prime (666584257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333292125 + 333292126.

It is an arithmetic number, because the mean of its divisors is an integer number (333292126).

Almost surely, 2^666584251 is an apocalyptic number.

666584251 is a deficient number, since it is larger than the sum of its proper divisors (1).

666584251 is an equidigital number, since it uses as much as digits as its factorization.

666584251 is an evil number, because the sum of its binary digits is even.

The product of its digits is 345600, while the sum is 43.

The square root of 666584251 is about 25818.2929528658. The cubic root of 666584251 is about 873.5444648946.

The spelling of 666584251 in words is "six hundred sixty-six million, five hundred eighty-four thousand, two hundred fifty-one".