20355253401617 has 2 divisors, whose sum is σ = 20355253401618. Its totient is φ = 20355253401616.

The previous prime is 20355253401547. The next prime is 20355253401697. The reversal of 20355253401617 is 71610435255302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13570942383376 + 6784311018241 = 3683876^2 + 2604671^2 .

It is a cyclic number.

It is not a de Polignac number, because 20355253401617 - 2²² = 20355249207313 is a prime.

It is not a weakly prime, because it can be changed into another prime (20355253401697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10177626700808 + 10177626700809.

It is an arithmetic number, because the mean of its divisors is an integer number (10177626700809).

Almost surely, 2^{20355253401617} is an apocalyptic number.

It is an amenable number.

20355253401617 is a deficient number, since it is larger than the sum of its proper divisors (1).

20355253401617 is an equidigital number, since it uses as much as digits as its factorization.

20355253401617 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 756000, while the sum is 44.

Adding to 20355253401617 its reverse (71610435255302), we get a palindrome (91965688656919).

The spelling of 20355253401617 in words is "twenty trillion, three hundred fifty-five billion, two hundred fifty-three million, four hundred one thousand, six hundred seventeen".