28885721764 has 9 divisors (see below), whose sum is σ = 50550607947. Its totient is φ = 14442690924.

The previous prime is 28885721747. The next prime is 28885721779. The reversal of 28885721764 is 46712758882.

It is a happy number.

The square root of 28885721764 is 169958.

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

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28885721699 and 28885721708.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 297427 + ... + 382405.

Almost surely, 2^28885721764 is an apocalyptic number.

28885721764 is the 169958-th square number.

It is an amenable number.

28885721764 is a deficient number, since it is larger than the sum of its proper divisors (21664886183).

28885721764 is an frugal number, since it uses more digits than its factorization.

28885721764 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 169962 (or 84981 counting only the distinct ones).

The product of its digits is 12042240, while the sum is 58.

The spelling of 28885721764 in words is "twenty-eight billion, eight hundred eighty-five million, seven hundred twenty-one thousand, seven hundred sixty-four".