1221221200213 has 24 divisors (see below), whose sum is σ = 1504447320024. Its totient is φ = 985004697600.

The previous prime is 1221221200211. The next prime is 1221221200217. The reversal of 1221221200213 is 3120021221221.

It can be written as a sum of positive squares in 4 ways, for example, as 223825502404 + 997395697809 = 473102^2 + 998697^2 .

It is not a de Polignac number, because 1221221200213 - 2¹ = 1221221200211 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221221200211) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4466223 + ... + 4731763.

It is an arithmetic number, because the mean of its divisors is an integer number (62685305001).

Almost surely, 2^{1221221200213} is an apocalyptic number.

It is an amenable number.

1221221200213 is a deficient number, since it is larger than the sum of its proper divisors (283226119811).

1221221200213 is a wasteful number, since it uses less digits than its factorization.

1221221200213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271093 (or 271086 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 1221221200213 its reverse (3120021221221), we get a palindrome (4341242421434).

The spelling of 1221221200213 in words is "one trillion, two hundred twenty-one billion, two hundred twenty-one million, two hundred thousand, two hundred thirteen".