666354523 has 2 divisors, whose sum is σ = 666354524. Its totient is φ = 666354522.

The previous prime is 666354511. The next prime is 666354539. The reversal of 666354523 is 325453666.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 666354523 - 2⁹ = 666354011 is a prime.

It is equal to p_34599055 and since 666354523 and 34599055 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (666354553) 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, 333177261 + 333177262.

It is an arithmetic number, because the mean of its divisors is an integer number (333177262).

Almost surely, 2^666354523 is an apocalyptic number.

666354523 is a deficient number, since it is larger than the sum of its proper divisors (1).

666354523 is an equidigital number, since it uses as much as digits as its factorization.

666354523 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 388800, while the sum is 40.

The square root of 666354523 is about 25813.8436308892. The cubic root of 666354523 is about 873.4441021470. Note that the first 3 decimals are identical.

The spelling of 666354523 in words is "six hundred sixty-six million, three hundred fifty-four thousand, five hundred twenty-three".