1221510112013 has 2 divisors, whose sum is σ = 1221510112014. Its totient is φ = 1221510112012.

The previous prime is 1221510111979. The next prime is 1221510112021. The reversal of 1221510112013 is 3102110151221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 847537501924 + 373972610089 = 920618^2 + 611533^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221510112013 - 2²⁴ = 1221493334797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221510112073) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610755056006 + 610755056007.

It is an arithmetic number, because the mean of its divisors is an integer number (610755056007).

Almost surely, 2^{1221510112013} is an apocalyptic number.

It is an amenable number.

1221510112013 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221510112013 is an equidigital number, since it uses as much as digits as its factorization.

1221510112013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 120, while the sum is 20.

Adding to 1221510112013 its reverse (3102110151221), we get a palindrome (4323620263234).

The spelling of 1221510112013 in words is "one trillion, two hundred twenty-one billion, five hundred ten million, one hundred twelve thousand, thirteen".