20354143203617 has 2 divisors, whose sum is σ = 20354143203618. Its totient is φ = 20354143203616.

The previous prime is 20354143203599. The next prime is 20354143203673. The reversal of 20354143203617 is 71630234145302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15591094485136 + 4763048718481 = 3948556^2 + 2182441^2 .

It is a cyclic number.

It is not a de Polignac number, because 20354143203617 - 2²² = 20354139009313 is a prime.

It is a super-2 number, since 2×20354143203617² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20354143203697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10177071601808 + 10177071601809.

It is an arithmetic number, because the mean of its divisors is an integer number (10177071601809).

Almost surely, 2^{20354143203617} is an apocalyptic number.

It is an amenable number.

20354143203617 is a deficient number, since it is larger than the sum of its proper divisors (1).

20354143203617 is an equidigital number, since it uses as much as digits as its factorization.

20354143203617 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 362880, while the sum is 41.

Adding to 20354143203617 its reverse (71630234145302), we get a palindrome (91984377348919).

The spelling of 20354143203617 in words is "twenty trillion, three hundred fifty-four billion, one hundred forty-three million, two hundred three thousand, six hundred seventeen".