1228210121 has 2 divisors, whose sum is σ = 1228210122. Its totient is φ = 1228210120.

The previous prime is 1228210099. The next prime is 1228210163. The reversal of 1228210121 is 1210128221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 974126521 + 254083600 = 31211^2 + 15940^2 .

It is a cyclic number.

It is not a de Polignac number, because 1228210121 - 2¹⁰ = 1228209097 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1228210093 and 1228210102.

It is not a weakly prime, because it can be changed into another prime (1228210171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 614105060 + 614105061.

It is an arithmetic number, because the mean of its divisors is an integer number (614105061).

Almost surely, 2^1228210121 is an apocalyptic number.

It is an amenable number.

1228210121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1228210121 is an equidigital number, since it uses as much as digits as its factorization.

1228210121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 128, while the sum is 20.

The square root of 1228210121 is about 35045.8288673560. The cubic root of 1228210121 is about 1070.9213018835.

Adding to 1228210121 its reverse (1210128221), we get a palindrome (2438338342).

The spelling of 1228210121 in words is "one billion, two hundred twenty-eight million, two hundred ten thousand, one hundred twenty-one".