20566706729 has 2 divisors, whose sum is σ = 20566706730. Its totient is φ = 20566706728.

The previous prime is 20566706723. The next prime is 20566706749. The reversal of 20566706729 is 92760766502.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20519989504 + 46717225 = 143248^2 + 6835^2 .

It is a cyclic number.

It is not a de Polignac number, because 20566706729 - 2³² = 16271739433 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (20566706723) 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, 10283353364 + 10283353365.

It is an arithmetic number, because the mean of its divisors is an integer number (10283353365).

Almost surely, 2^20566706729 is an apocalyptic number.

It is an amenable number.

20566706729 is a deficient number, since it is larger than the sum of its proper divisors (1).

20566706729 is an equidigital number, since it uses as much as digits as its factorization.

20566706729 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1905120, while the sum is 50.

The spelling of 20566706729 in words is "twenty billion, five hundred sixty-six million, seven hundred six thousand, seven hundred twenty-nine".