665312213566 has 192 divisors, whose sum is σ = 1374578569728. Its totient is φ = 234967392000.

The previous prime is 665312213557. The next prime is 665312213593.

665312213566 is nontrivially palindromic in base 10.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 330835501 + ... + 330837511.

It is an arithmetic number, because the mean of its divisors is an integer number (7159263384).

Almost surely, 2^665312213566 is an apocalyptic number.

665312213566 is an abundant number, since it is smaller than the sum of its proper divisors (709266356162).

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

665312213566 is a wasteful number, since it uses less digits than its factorization.

665312213566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2319 (or 2308 counting only the distinct ones).

The product of its digits is 1166400, while the sum is 46.

It can be divided in two parts, 665312 and 213566, that added together give a palindrome (878878).

The spelling of 665312213566 in words is "six hundred sixty-five billion, three hundred twelve million, two hundred thirteen thousand, five hundred sixty-six".