665523563 has 2 divisors, whose sum is σ = 665523564. Its totient is φ = 665523562.

The previous prime is 665523559. The next prime is 665523569. The reversal of 665523563 is 365325566.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 665523563 - 2² = 665523559 is a prime.

It is a super-2 number, since 2×665523563² = 885843225816429938, which contains 22 as substring.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 665523563.

It is not a weakly prime, because it can be changed into another prime (665523569) 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, 332761781 + 332761782.

It is an arithmetic number, because the mean of its divisors is an integer number (332761782).

Almost surely, 2^665523563 is an apocalyptic number.

665523563 is a deficient number, since it is larger than the sum of its proper divisors (1).

665523563 is an equidigital number, since it uses as much as digits as its factorization.

665523563 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 486000, while the sum is 41.

The square root of 665523563 is about 25797.7433703028. The cubic root of 665523563 is about 873.0808825741.

The spelling of 665523563 in words is "six hundred sixty-five million, five hundred twenty-three thousand, five hundred sixty-three".