221001021200161 has 2 divisors, whose sum is σ = 221001021200162. Its totient is φ = 221001021200160.

The previous prime is 221001021200131. The next prime is 221001021200213. The reversal of 221001021200161 is 161002120100122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 201145263439761 + 19855757760400 = 14182569^2 + 4455980^2 .

It is a cyclic number.

It is not a de Polignac number, because 221001021200161 - 2⁵ = 221001021200129 is a prime.

It is not a weakly prime, because it can be changed into another prime (221001021200131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110500510600080 + 110500510600081.

It is an arithmetic number, because the mean of its divisors is an integer number (110500510600081).

Almost surely, 2^{221001021200161} is an apocalyptic number.

It is an amenable number.

221001021200161 is a deficient number, since it is larger than the sum of its proper divisors (1).

221001021200161 is an equidigital number, since it uses as much as digits as its factorization.

221001021200161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 19.

Adding to 221001021200161 its reverse (161002120100122), we get a palindrome (382003141300283).

The spelling of 221001021200161 in words is "two hundred twenty-one trillion, one billion, twenty-one million, two hundred thousand, one hundred sixty-one".