666126563 has 2 divisors, whose sum is σ = 666126564. Its totient is φ = 666126562.

The previous prime is 666126551. The next prime is 666126581. The reversal of 666126563 is 365621666.

It is a happy number.

666126563 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 666126563 - 2⁴ = 666126547 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 666126563.

It is not a weakly prime, because it can be changed into another prime (666126523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333063281 + 333063282.

It is an arithmetic number, because the mean of its divisors is an integer number (333063282).

Almost surely, 2^666126563 is an apocalyptic number.

666126563 is a deficient number, since it is larger than the sum of its proper divisors (1).

666126563 is an equidigital number, since it uses as much as digits as its factorization.

666126563 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 233280, while the sum is 41.

The square root of 666126563 is about 25809.4277929597. The cubic root of 666126563 is about 873.3444889931.

The spelling of 666126563 in words is "six hundred sixty-six million, one hundred twenty-six thousand, five hundred sixty-three".