20017506442121 has 2 divisors, whose sum is σ = 20017506442122. Its totient is φ = 20017506442120.

The previous prime is 20017506442019. The next prime is 20017506442139. The reversal of 20017506442121 is 12124460571002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15216521498896 + 4800984943225 = 3900836^2 + 2191115^2 .

It is a cyclic number.

It is not a de Polignac number, because 20017506442121 - 2¹⁸ = 20017506179977 is a prime.

It is not a weakly prime, because it can be changed into another prime (20017106442121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10008753221060 + 10008753221061.

It is an arithmetic number, because the mean of its divisors is an integer number (10008753221061).

Almost surely, 2^{20017506442121} is an apocalyptic number.

It is an amenable number.

20017506442121 is a deficient number, since it is larger than the sum of its proper divisors (1).

20017506442121 is an equidigital number, since it uses as much as digits as its factorization.

20017506442121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 26880, while the sum is 35.

The spelling of 20017506442121 in words is "twenty trillion, seventeen billion, five hundred six million, four hundred forty-two thousand, one hundred twenty-one".