1231003220221 has 2 divisors, whose sum is σ = 1231003220222. Its totient is φ = 1231003220220.

The previous prime is 1231003220171. The next prime is 1231003220233. The reversal of 1231003220221 is 1220223001321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1094095080100 + 136908140121 = 1045990^2 + 370011^2 .

It is an emirp because it is prime and its reverse (1220223001321) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1231003220221 - 2¹³ = 1231003212029 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1231003220921) 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, 615501610110 + 615501610111.

It is an arithmetic number, because the mean of its divisors is an integer number (615501610111).

Almost surely, 2^{1231003220221} is an apocalyptic number.

It is an amenable number.

1231003220221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231003220221 is an equidigital number, since it uses as much as digits as its factorization.

1231003220221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 1231003220221 its reverse (1220223001321), we get a palindrome (2451226221542).

The spelling of 1231003220221 in words is "one trillion, two hundred thirty-one billion, three million, two hundred twenty thousand, two hundred twenty-one".