1221303223213 has 4 divisors (see below), whose sum is σ = 1251091106748. Its totient is φ = 1191515339680.

The previous prime is 1221303223211. The next prime is 1221303223291. The reversal of 1221303223213 is 3123223031221.

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 51265110724 + 1170038112489 = 226418^2 + 1081683^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221303223213 - 2¹ = 1221303223211 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 (1221303223211) 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, 14893941706 + ... + 14893941787.

It is an arithmetic number, because the mean of its divisors is an integer number (312772776687).

Almost surely, 2^{1221303223213} is an apocalyptic number.

It is an amenable number.

1221303223213 is a deficient number, since it is larger than the sum of its proper divisors (29787883535).

1221303223213 is an equidigital number, since it uses as much as digits as its factorization.

1221303223213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29787883534.

The product of its (nonzero) digits is 2592, while the sum is 25.

Adding to 1221303223213 its reverse (3123223031221), we get a palindrome (4344526254434).

The spelling of 1221303223213 in words is "one trillion, two hundred twenty-one billion, three hundred three million, two hundred twenty-three thousand, two hundred thirteen".