20529169657 has 2 divisors, whose sum is σ = 20529169658. Its totient is φ = 20529169656.

The previous prime is 20529169631. The next prime is 20529169691. The reversal of 20529169657 is 75696192502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12828054121 + 7701115536 = 113261^2 + 87756^2 .

It is a cyclic number.

It is not a de Polignac number, because 20529169657 - 2¹¹ = 20529167609 is a prime.

It is not a weakly prime, because it can be changed into another prime (20529160657) 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, 10264584828 + 10264584829.

It is an arithmetic number, because the mean of its divisors is an integer number (10264584829).

Almost surely, 2^20529169657 is an apocalyptic number.

It is an amenable number.

20529169657 is a deficient number, since it is larger than the sum of its proper divisors (1).

20529169657 is an equidigital number, since it uses as much as digits as its factorization.

20529169657 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2041200, while the sum is 52.

The spelling of 20529169657 in words is "twenty billion, five hundred twenty-nine million, one hundred sixty-nine thousand, six hundred fifty-seven".