20972730563 has 4 divisors (see below), whose sum is σ = 20973048600. Its totient is φ = 20972412528.

The previous prime is 20972730557. The next prime is 20972730589. The reversal of 20972730563 is 36503727902.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20972730563 - 2¹⁶ = 20972665027 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20972730503) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19013 + ... + 205686.

It is an arithmetic number, because the mean of its divisors is an integer number (5243262150).

Almost surely, 2^20972730563 is an apocalyptic number.

20972730563 is a deficient number, since it is larger than the sum of its proper divisors (318037).

20972730563 is an equidigital number, since it uses as much as digits as its factorization.

20972730563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 318036.

The product of its (nonzero) digits is 476280, while the sum is 44.

The spelling of 20972730563 in words is "twenty billion, nine hundred seventy-two million, seven hundred thirty thousand, five hundred sixty-three".