664526563 has 2 divisors, whose sum is σ = 664526564. Its totient is φ = 664526562.

The previous prime is 664526543. The next prime is 664526573. The reversal of 664526563 is 365625466.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-664526563 is a prime.

It is not a weakly prime, because it can be changed into another prime (664526543) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332263281 + 332263282.

It is an arithmetic number, because the mean of its divisors is an integer number (332263282).

Almost surely, 2^664526563 is an apocalyptic number.

664526563 is a deficient number, since it is larger than the sum of its proper divisors (1).

664526563 is an equidigital number, since it uses as much as digits as its factorization.

664526563 is an evil number, because the sum of its binary digits is even.

The product of its digits is 777600, while the sum is 43.

The square root of 664526563 is about 25778.4127323619. The cubic root of 664526563 is about 872.6446863116.

The spelling of 664526563 in words is "six hundred sixty-four million, five hundred twenty-six thousand, five hundred sixty-three".