20994850816 has 57 divisors (see below), whose sum is σ = 42138519051. Its totient is φ = 10460332032.

The previous prime is 20994850691. The next prime is 20994850819. The reversal of 20994850816 is 61805849902.

The square root of 20994850816 is 144896.

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

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20994850819) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 74186611 + ... + 74186893.

Almost surely, 2^20994850816 is an apocalyptic number.

20994850816 is the 144896-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20994850816

20994850816 is an abundant number, since it is smaller than the sum of its proper divisors (21143668235).

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

20994850816 is an frugal number, since it uses more digits than its factorization.

20994850816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 602 (or 285 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 52.

The spelling of 20994850816 in words is "twenty billion, nine hundred ninety-four million, eight hundred fifty thousand, eight hundred sixteen".