221020121200171 has 2 divisors, whose sum is σ = 221020121200172. Its totient is φ = 221020121200170.

The previous prime is 221020121200117. The next prime is 221020121200237. The reversal of 221020121200171 is 171002121020122.

Together with previous prime (221020121200117) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221020121200171 is a prime.

It is not a weakly prime, because it can be changed into another prime (221020121201171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110510060600085 + 110510060600086.

It is an arithmetic number, because the mean of its divisors is an integer number (110510060600086).

Almost surely, 2^{221020121200171} is an apocalyptic number.

221020121200171 is a deficient number, since it is larger than the sum of its proper divisors (1).

221020121200171 is an equidigital number, since it uses as much as digits as its factorization.

221020121200171 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 224, while the sum is 22.

Adding to 221020121200171 its reverse (171002121020122), we get a palindrome (392022242220293).

The spelling of 221020121200171 in words is "two hundred twenty-one trillion, twenty billion, one hundred twenty-one million, two hundred thousand, one hundred seventy-one".