20617145663 has 2 divisors, whose sum is σ = 20617145664. Its totient is φ = 20617145662.

The previous prime is 20617145623. The next prime is 20617145687. The reversal of 20617145663 is 36654171602.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20617145663 - 2¹⁸ = 20616883519 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20617145663.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20617145623) 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, 10308572831 + 10308572832.

It is an arithmetic number, because the mean of its divisors is an integer number (10308572832).

Almost surely, 2^20617145663 is an apocalyptic number.

20617145663 is a deficient number, since it is larger than the sum of its proper divisors (1).

20617145663 is an equidigital number, since it uses as much as digits as its factorization.

20617145663 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 181440, while the sum is 41.

The spelling of 20617145663 in words is "twenty billion, six hundred seventeen million, one hundred forty-five thousand, six hundred sixty-three".