666662047 has 2 divisors, whose sum is σ = 666662048. Its totient is φ = 666662046.

The previous prime is 666662039. The next prime is 666662071. The reversal of 666662047 is 740266666.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 666662047 - 2³ = 666662039 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 666661994 and 666662012.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666662027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333331023 + 333331024.

It is an arithmetic number, because the mean of its divisors is an integer number (333331024).

Almost surely, 2^666662047 is an apocalyptic number.

666662047 is a deficient number, since it is larger than the sum of its proper divisors (1).

666662047 is an equidigital number, since it uses as much as digits as its factorization.

666662047 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 435456, while the sum is 43.

The square root of 666662047 is about 25819.7995151008. The cubic root of 666662047 is about 873.5784469064.

The spelling of 666662047 in words is "six hundred sixty-six million, six hundred sixty-two thousand, forty-seven".