1231012112221 has 2 divisors, whose sum is σ = 1231012112222. Its totient is φ = 1231012112220.

The previous prime is 1231012112219. The next prime is 1231012112299. The reversal of 1231012112221 is 1222112101321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1151459909721 + 79552202500 = 1073061^2 + 282050^2 .

It is an emirp because it is prime and its reverse (1222112101321) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1231012112221 - 2¹ = 1231012112219 is a prime.

Together with 1231012112219, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1231012118221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615506056110 + 615506056111.

It is an arithmetic number, because the mean of its divisors is an integer number (615506056111).

Almost surely, 2^{1231012112221} is an apocalyptic number.

It is an amenable number.

1231012112221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231012112221 is an equidigital number, since it uses as much as digits as its factorization.

1231012112221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 19.

Adding to 1231012112221 its reverse (1222112101321), we get a palindrome (2453124213542).

It can be divided in two parts, 123101 and 2112221, that added together give a palindrome (2235322).

The spelling of 1231012112221 in words is "one trillion, two hundred thirty-one billion, twelve million, one hundred twelve thousand, two hundred twenty-one".