1221220111253 has 2 divisors, whose sum is σ = 1221220111254. Its totient is φ = 1221220111252.

The previous prime is 1221220111219. The next prime is 1221220111273. The reversal of 1221220111253 is 3521110221221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1010702483569 + 210517627684 = 1005337^2 + 458822^2 .

It is an emirp because it is prime and its reverse (3521110221221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1221220111253 - 2¹² = 1221220107157 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221220111273) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610610055626 + 610610055627.

It is an arithmetic number, because the mean of its divisors is an integer number (610610055627).

Almost surely, 2^{1221220111253} is an apocalyptic number.

It is an amenable number.

1221220111253 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221220111253 is an equidigital number, since it uses as much as digits as its factorization.

1221220111253 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 480, while the sum is 23.

Adding to 1221220111253 its reverse (3521110221221), we get a palindrome (4742330332474).

The spelling of 1221220111253 in words is "one trillion, two hundred twenty-one billion, two hundred twenty million, one hundred eleven thousand, two hundred fifty-three".