1220221110161 has 2 divisors, whose sum is σ = 1220221110162. Its totient is φ = 1220221110160.

The previous prime is 1220221110139. The next prime is 1220221110169. The reversal of 1220221110161 is 1610111220221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 912827376400 + 307393733761 = 955420^2 + 554431^2 .

It is a cyclic number.

It is not a de Polignac number, because 1220221110161 - 2¹⁰ = 1220221109137 is a prime.

It is not a weakly prime, because it can be changed into another prime (1220221110169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610110555080 + 610110555081.

It is an arithmetic number, because the mean of its divisors is an integer number (610110555081).

Almost surely, 2^{1220221110161} is an apocalyptic number.

It is an amenable number.

1220221110161 is a deficient number, since it is larger than the sum of its proper divisors (1).

1220221110161 is an equidigital number, since it uses as much as digits as its factorization.

1220221110161 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 20.

Adding to 1220221110161 its reverse (1610111220221), we get a palindrome (2830332330382).

The spelling of 1220221110161 in words is "one trillion, two hundred twenty billion, two hundred twenty-one million, one hundred ten thousand, one hundred sixty-one".