20565542443 has 2 divisors, whose sum is σ = 20565542444. Its totient is φ = 20565542442.

The previous prime is 20565542401. The next prime is 20565542453. The reversal of 20565542443 is 34424556502.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20565542443 - 2²¹ = 20563445291 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20565542396 and 20565542405.

It is not a weakly prime, because it can be changed into another prime (20565542453) 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 as a sum of consecutive naturals, namely, 10282771221 + 10282771222.

It is an arithmetic number, because the mean of its divisors is an integer number (10282771222).

Almost surely, 2^20565542443 is an apocalyptic number.

20565542443 is a deficient number, since it is larger than the sum of its proper divisors (1).

20565542443 is an equidigital number, since it uses as much as digits as its factorization.

20565542443 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 576000, while the sum is 40.

The spelling of 20565542443 in words is "twenty billion, five hundred sixty-five million, five hundred forty-two thousand, four hundred forty-three".