1321204013 has 2 divisors, whose sum is σ = 1321204014. Its totient is φ = 1321204012.

The previous prime is 1321203971. The next prime is 1321204039. The reversal of 1321204013 is 3104021231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 721835689 + 599368324 = 26867^2 + 24482^2 .

It is a cyclic number.

It is not a de Polignac number, because 1321204013 - 2¹⁶ = 1321138477 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1321203982 and 1321204000.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1321504013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660602006 + 660602007.

It is an arithmetic number, because the mean of its divisors is an integer number (660602007).

Almost surely, 2^1321204013 is an apocalyptic number.

It is an amenable number.

1321204013 is a deficient number, since it is larger than the sum of its proper divisors (1).

1321204013 is an equidigital number, since it uses as much as digits as its factorization.

1321204013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 1321204013 is about 36348.3701560331. The cubic root of 1321204013 is about 1097.2947332932.

Adding to 1321204013 its reverse (3104021231), we get a palindrome (4425225244).

The spelling of 1321204013 in words is "one billion, three hundred twenty-one million, two hundred four thousand, thirteen".