665516810550 has 48 divisors (see below), whose sum is σ = 1650614443200. Its totient is φ = 177456875040.

The previous prime is 665516810531. The next prime is 665516810551. The reversal of 665516810550 is 55018615566.

It is a self number, because there is not a number n which added to its sum of digits gives 665516810550.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665516810551) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1762869 + ... + 2106831.

It is an arithmetic number, because the mean of its divisors is an integer number (34387800900).

Almost surely, 2^665516810550 is an apocalyptic number.

665516810550 is an abundant number, since it is smaller than the sum of its proper divisors (985097632650).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

665516810550 is a wasteful number, since it uses less digits than its factorization.

665516810550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 356877 (or 356872 counting only the distinct ones).

The product of its (nonzero) digits is 1080000, while the sum is 48.

The spelling of 665516810550 in words is "six hundred sixty-five billion, five hundred sixteen million, eight hundred ten thousand, five hundred fifty".