866225568884568 has 128 divisors (see below), whose sum is σ = 2323790290944000. Its totient is φ = 268107279298560.

The previous prime is 866225568884539. The next prime is 866225568884579. The reversal of 866225568884568 is 865488865522668.

It is a happy number.

It is a super-2 number, since 2×866225568884568² (a number of 31 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 30718588 + ... + 51730868.

It is an arithmetic number, because the mean of its divisors is an integer number (18154611648000).

Almost surely, 2^{866225568884568} 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 866225568884568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1161895145472000).

866225568884568 is an abundant number, since it is smaller than the sum of its proper divisors (1457564722059432).

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

866225568884568 is a wasteful number, since it uses less digits than its factorization.

866225568884568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21013665 (or 21013661 counting only the distinct ones).

The product of its digits is 84934656000, while the sum is 87.

The spelling of 866225568884568 in words is "eight hundred sixty-six trillion, two hundred twenty-five billion, five hundred sixty-eight million, eight hundred eighty-four thousand, five hundred sixty-eight".