663205818616 has 64 divisors (see below), whose sum is σ = 1416496481280. Its totient is φ = 288155134080.

The previous prime is 663205818607. The next prime is 663205818617. The reversal of 663205818616 is 616818502366.

It is a super-2 number, since 2×663205818616² (a number of 24 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (52) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (663205818617) 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 15 ways as a sum of consecutive naturals, for example, 2899510 + ... + 3119866.

It is an arithmetic number, because the mean of its divisors is an integer number (22132757520).

Almost surely, 2^663205818616 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 663205818616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (708248240640).

663205818616 is an abundant number, since it is smaller than the sum of its proper divisors (753290662664).

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

663205818616 is a wasteful number, since it uses less digits than its factorization.

663205818616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221884 (or 221880 counting only the distinct ones).

The product of its (nonzero) digits is 2488320, while the sum is 52.

The spelling of 663205818616 in words is "six hundred sixty-three billion, two hundred five million, eight hundred eighteen thousand, six hundred sixteen".