20555210317 has 2 divisors, whose sum is σ = 20555210318. Its totient is φ = 20555210316.

The previous prime is 20555210311. The next prime is 20555210341. The reversal of 20555210317 is 71301255502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17607697636 + 2947512681 = 132694^2 + 54291^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20555210317 is a prime.

It is a super-2 number, since 2×20555210317² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20555210311) 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, 10277605158 + 10277605159.

It is an arithmetic number, because the mean of its divisors is an integer number (10277605159).

Almost surely, 2^20555210317 is an apocalyptic number.

It is an amenable number.

20555210317 is a deficient number, since it is larger than the sum of its proper divisors (1).

20555210317 is an equidigital number, since it uses as much as digits as its factorization.

20555210317 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10500, while the sum is 31.

Adding to 20555210317 its reverse (71301255502), we get a palindrome (91856465819).

The spelling of 20555210317 in words is "twenty billion, five hundred fifty-five million, two hundred ten thousand, three hundred seventeen".