1221100020013 has 2 divisors, whose sum is σ = 1221100020014. Its totient is φ = 1221100020012.

The previous prime is 1221100019999. The next prime is 1221100020029. The reversal of 1221100020013 is 3100200011221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 775734654564 + 445365365449 = 880758^2 + 667357^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221100020013 - 2²⁹ = 1220563149101 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1221100019975 and 1221100020002.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221100020053) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610550010006 + 610550010007.

It is an arithmetic number, because the mean of its divisors is an integer number (610550010007).

Almost surely, 2^{1221100020013} is an apocalyptic number.

It is an amenable number.

1221100020013 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221100020013 is an equidigital number, since it uses as much as digits as its factorization.

1221100020013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 1221100020013 its reverse (3100200011221), we get a palindrome (4321300031234).

The spelling of 1221100020013 in words is "one trillion, two hundred twenty-one billion, one hundred million, twenty thousand, thirteen".