20504345569 has 2 divisors, whose sum is σ = 20504345570. Its totient is φ = 20504345568.

The previous prime is 20504345527. The next prime is 20504345581. The reversal of 20504345569 is 96554340502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16955164944 + 3549180625 = 130212^2 + 59575^2 .

It is a cyclic number.

It is not a de Polignac number, because 20504345569 - 2¹³ = 20504337377 is a prime.

It is a super-2 number, since 2×20504345569² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20504375569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10252172784 + 10252172785.

It is an arithmetic number, because the mean of its divisors is an integer number (10252172785).

Almost surely, 2^20504345569 is an apocalyptic number.

It is an amenable number.

20504345569 is a deficient number, since it is larger than the sum of its proper divisors (1).

20504345569 is an equidigital number, since it uses as much as digits as its factorization.

20504345569 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648000, while the sum is 43.

The spelling of 20504345569 in words is "twenty billion, five hundred four million, three hundred forty-five thousand, five hundred sixty-nine".