864621022500 has 135 divisors (see below), whose sum is σ = 2731528670871. Its totient is φ = 230528412000.

The previous prime is 864621022453. The next prime is 864621022523. The reversal of 864621022500 is 5220126468.

It is a happy number.

The square root of 864621022500 is 929850.

It is a perfect power (a square), and thus also a powerful number.

864621022500 is a `hidden beast` number, since 8 + 6 + 4 + 621 + 0 + 2 + 25 + 0 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 67786288164 + 796834734336 = 260358^2 + 892656^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 139474401 + ... + 139480599.

Almost surely, 2^864621022500 is an apocalyptic number.

864621022500 is the 929850-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 864621022500

864621022500 is an abundant number, since it is smaller than the sum of its proper divisors (1866907648371).

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

864621022500 is an frugal number, since it uses more digits than its factorization.

864621022500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12428 (or 6209 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

Multiplying 864621022500 by its sum of digits (36), we get a square (31126356810000 = 5579100²).

864621022500 divided by its sum of digits (36) gives a square (24017250625 = 154975²).

Adding to 864621022500 its reverse (5220126468), we get a palindrome (869841148968).

The spelling of 864621022500 in words is "eight hundred sixty-four billion, six hundred twenty-one million, twenty-two thousand, five hundred".