201221389 has 2 divisors, whose sum is σ = 201221390. Its totient is φ = 201221388.

The previous prime is 201221351. The next prime is 201221417. The reversal of 201221389 is 983122102.

It is an a-pointer prime, because the next prime (201221417) can be obtained adding 201221389 to its sum of digits (28).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 128255625 + 72965764 = 11325^2 + 8542^2 .

It is a cyclic number.

It is not a de Polignac number, because 201221389 - 2⁷ = 201221261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (201221309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100610694 + 100610695.

It is an arithmetic number, because the mean of its divisors is an integer number (100610695).

Almost surely, 2^201221389 is an apocalyptic number.

It is an amenable number.

201221389 is a deficient number, since it is larger than the sum of its proper divisors (1).

201221389 is an equidigital number, since it uses as much as digits as its factorization.

201221389 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 201221389 is about 14185.2525180203. The cubic root of 201221389 is about 585.9915868517.

The spelling of 201221389 in words is "two hundred one million, two hundred twenty-one thousand, three hundred eighty-nine".