1220166161 has 2 divisors, whose sum is σ = 1220166162. Its totient is φ = 1220166160.

The previous prime is 1220166133. The next prime is 1220166193. The reversal of 1220166161 is 1616610221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 933913600 + 286252561 = 30560^2 + 16919^2 .

It is a cyclic number.

It is not a de Polignac number, because 1220166161 - 2¹⁰ = 1220165137 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1220166161.

It is not a weakly prime, because it can be changed into another prime (1220166121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610083080 + 610083081.

It is an arithmetic number, because the mean of its divisors is an integer number (610083081).

Almost surely, 2^1220166161 is an apocalyptic number.

It is an amenable number.

1220166161 is a deficient number, since it is larger than the sum of its proper divisors (1).

1220166161 is an equidigital number, since it uses as much as digits as its factorization.

1220166161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 1220166161 is about 34930.8768999577. The cubic root of 1220166161 is about 1068.5782383206.

Adding to 1220166161 its reverse (1616610221), we get a palindrome (2836776382).

The spelling of 1220166161 in words is "one billion, two hundred twenty million, one hundred sixty-six thousand, one hundred sixty-one".