1221313203 has 12 divisors (see below), whose sum is σ = 1924493688. Its totient is φ = 740189760.

The previous prime is 1221313193. The next prime is 1221313213. The reversal of 1221313203 is 3023131221.

It is an interprime number because it is at equal distance from previous prime (1221313193) and next prime (1221313213).

It is not a de Polignac number, because 1221313203 - 2⁴ = 1221313187 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1221313213) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6168150 + ... + 6168347.

It is an arithmetic number, because the mean of its divisors is an integer number (160374474).

Almost surely, 2^1221313203 is an apocalyptic number.

1221313203 is a deficient number, since it is larger than the sum of its proper divisors (703180485).

1221313203 is a wasteful number, since it uses less digits than its factorization.

1221313203 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12336514 (or 12336511 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 1221313203 is about 34947.2917834845. The cubic root of 1221313203 is about 1068.9129796798.

Adding to 1221313203 its reverse (3023131221), we get a palindrome (4244444424).

The spelling of 1221313203 in words is "one billion, two hundred twenty-one million, three hundred thirteen thousand, two hundred three".