665005563 has 6 divisors (see below), whose sum is σ = 960563604. Its totient is φ = 443337036.

The previous prime is 665005553. The next prime is 665005571. The reversal of 665005563 is 365500566.

It is a happy number.

It is not a de Polignac number, because 665005563 - 2⁵ = 665005531 is a prime.

It is not an unprimeable number, because it can be changed into a prime (665005553) 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 in 5 ways as a sum of consecutive naturals, for example, 36944745 + ... + 36944762.

It is an arithmetic number, because the mean of its divisors is an integer number (160093934).

Almost surely, 2^665005563 is an apocalyptic number.

665005563 is a deficient number, since it is larger than the sum of its proper divisors (295558041).

665005563 is a wasteful number, since it uses less digits than its factorization.

665005563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73889513 (or 73889510 counting only the distinct ones).

The product of its (nonzero) digits is 81000, while the sum is 36.

The square root of 665005563 is about 25787.7017781733. The cubic root of 665005563 is about 872.8543074341.

The spelling of 665005563 in words is "six hundred sixty-five million, five thousand, five hundred sixty-three".