20823644416 has 81 divisors (see below), whose sum is σ = 43187544673. Its totient is φ = 10020469760.

The previous prime is 20823644399. The next prime is 20823644417. The reversal of 20823644416 is 61444632802.

The square root of 20823644416 is 144304.

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

It can be written as a sum of positive squares in only one way, i.e., 10919414016 + 9904230400 = 104496^2 + 99520^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20823644417) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 66956901 + ... + 66957211.

Almost surely, 2^20823644416 is an apocalyptic number.

20823644416 is the 144304-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20823644416

20823644416 is an abundant number, since it is smaller than the sum of its proper divisors (22363900257).

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

20823644416 is an frugal number, since it uses more digits than its factorization.

20823644416 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 696 (or 342 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 40.

The spelling of 20823644416 in words is "twenty billion, eight hundred twenty-three million, six hundred forty-four thousand, four hundred sixteen".