664971211 has 2 divisors, whose sum is σ = 664971212. Its totient is φ = 664971210.

The previous prime is 664971179. The next prime is 664971227. The reversal of 664971211 is 112179466.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 664971211 - 2⁵ = 664971179 is a prime.

It is a super-2 number, since 2×664971211² = 884373422917613042, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (664971311) 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, 332485605 + 332485606.

It is an arithmetic number, because the mean of its divisors is an integer number (332485606).

Almost surely, 2^664971211 is an apocalyptic number.

664971211 is a deficient number, since it is larger than the sum of its proper divisors (1).

664971211 is an equidigital number, since it uses as much as digits as its factorization.

664971211 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18144, while the sum is 37.

The square root of 664971211 is about 25787.0357156460. The cubic root of 664971211 is about 872.8392775812.

The spelling of 664971211 in words is "six hundred sixty-four million, nine hundred seventy-one thousand, two hundred eleven".