1210221689 has 2 divisors, whose sum is σ = 1210221690. Its totient is φ = 1210221688.

The previous prime is 1210221647. The next prime is 1210221697. The reversal of 1210221689 is 9861220121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 686178025 + 524043664 = 26195^2 + 22892^2 .

It is a cyclic number.

It is not a de Polignac number, because 1210221689 - 2²⁰ = 1209173113 is a prime.

It is not a weakly prime, because it can be changed into another prime (1210229689) 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, 605110844 + 605110845.

It is an arithmetic number, because the mean of its divisors is an integer number (605110845).

Almost surely, 2^1210221689 is an apocalyptic number.

It is an amenable number.

1210221689 is a deficient number, since it is larger than the sum of its proper divisors (1).

1210221689 is an equidigital number, since it uses as much as digits as its factorization.

1210221689 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 32.

The square root of 1210221689 is about 34788.2406712383. The cubic root of 1210221689 is about 1065.6673105596.

The spelling of 1210221689 in words is "one billion, two hundred ten million, two hundred twenty-one thousand, six hundred eighty-nine".