1221003211213 has 4 divisors (see below), whose sum is σ = 1221036761308. Its totient is φ = 1220969661120.

The previous prime is 1221003211201. The next prime is 1221003211273. The reversal of 1221003211213 is 3121123001221.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1073269064169 + 147734147044 = 1035987^2 + 384362^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221003211213 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 (1221003211273) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16720398 + ... + 16793263.

It is an arithmetic number, because the mean of its divisors is an integer number (305259190327).

Almost surely, 2^{1221003211213} is an apocalyptic number.

It is an amenable number.

1221003211213 is a deficient number, since it is larger than the sum of its proper divisors (33550095).

1221003211213 is an equidigital number, since it uses as much as digits as its factorization.

1221003211213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33550094.

The product of its (nonzero) digits is 144, while the sum is 19.

Adding to 1221003211213 its reverse (3121123001221), we get a palindrome (4342126212434).

The spelling of 1221003211213 in words is "one trillion, two hundred twenty-one billion, three million, two hundred eleven thousand, two hundred thirteen".