1221313403 has 2 divisors, whose sum is σ = 1221313404. Its totient is φ = 1221313402.

The previous prime is 1221313367. The next prime is 1221313411. The reversal of 1221313403 is 3043131221.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1221313403 - 2¹² = 1221309307 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (1221313463) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610656701 + 610656702.

It is an arithmetic number, because the mean of its divisors is an integer number (610656702).

Almost surely, 2^1221313403 is an apocalyptic number.

1221313403 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221313403 is an equidigital number, since it uses as much as digits as its factorization.

1221313403 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 1221313403 is about 34947.2946449364. The cubic root of 1221313403 is about 1068.9130380275.

Adding to 1221313403 its reverse (3043131221), we get a palindrome (4264444624).

The spelling of 1221313403 in words is "one billion, two hundred twenty-one million, three hundred thirteen thousand, four hundred three".