20563989729 has 4 divisors (see below), whose sum is σ = 27418652976. Its totient is φ = 13709326484.

The previous prime is 20563989727. The next prime is 20563989739. The reversal of 20563989729 is 92798936502.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20563989729 - 2¹ = 20563989727 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20563989727) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 3427331619 + ... + 3427331624.

It is an arithmetic number, because the mean of its divisors is an integer number (6854663244).

Almost surely, 2^20563989729 is an apocalyptic number.

It is an amenable number.

20563989729 is a deficient number, since it is larger than the sum of its proper divisors (6854663247).

20563989729 is an equidigital number, since it uses as much as digits as its factorization.

20563989729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6854663246.

The product of its (nonzero) digits is 14696640, while the sum is 60.

The spelling of 20563989729 in words is "twenty billion, five hundred sixty-three million, nine hundred eighty-nine thousand, seven hundred twenty-nine".