1221221210239 has 2 divisors, whose sum is σ = 1221221210240. Its totient is φ = 1221221210238.

The previous prime is 1221221210173. The next prime is 1221221210267. The reversal of 1221221210239 is 9320121221221.

It is an a-pointer prime, because the next prime (1221221210267) can be obtained adding 1221221210239 to its sum of digits (28).

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1221221210239 - 2⁹ = 1221221209727 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221221210269) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610610605119 + 610610605120.

It is an arithmetic number, because the mean of its divisors is an integer number (610610605120).

Almost surely, 2^{1221221210239} is an apocalyptic number.

1221221210239 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221221210239 is an equidigital number, since it uses as much as digits as its factorization.

1221221210239 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 spelling of 1221221210239 in words is "one trillion, two hundred twenty-one billion, two hundred twenty-one million, two hundred ten thousand, two hundred thirty-nine".