866295724656 has 640 divisors, whose sum is σ = 2591834112000. Its totient is φ = 248074444800.

The previous prime is 866295724649. The next prime is 866295724703. The reversal of 866295724656 is 656427592668.

It is a Smith number, since the sum of its digits (66) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 3624668185 + ... + 3624668423.

It is an arithmetic number, because the mean of its divisors is an integer number (4049740800).

Almost surely, 2^866295724656 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 866295724656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1295917056000).

866295724656 is an abundant number, since it is smaller than the sum of its proper divisors (1725538387344).

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

866295724656 is a wasteful number, since it uses less digits than its factorization.

866295724656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 453 (or 447 counting only the distinct ones).

The product of its digits is 261273600, while the sum is 66.

It can be divided in two parts, 866295 and 724656, that added together give a palindrome (1590951).

The spelling of 866295724656 in words is "eight hundred sixty-six billion, two hundred ninety-five million, seven hundred twenty-four thousand, six hundred fifty-six".