1321350509 has 2 divisors, whose sum is σ = 1321350510. Its totient is φ = 1321350508.

The previous prime is 1321350431. The next prime is 1321350521. The reversal of 1321350509 is 9050531231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1298521225 + 22829284 = 36035^2 + 4778^2 .

It is a cyclic number.

It is not a de Polignac number, because 1321350509 - 2²⁴ = 1304573293 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1321350539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660675254 + 660675255.

It is an arithmetic number, because the mean of its divisors is an integer number (660675255).

Almost surely, 2^1321350509 is an apocalyptic number.

It is an amenable number.

1321350509 is a deficient number, since it is larger than the sum of its proper divisors (1).

1321350509 is an equidigital number, since it uses as much as digits as its factorization.

1321350509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4050, while the sum is 29.

The square root of 1321350509 is about 36350.3852661839. The cubic root of 1321350509 is about 1097.3352880565.

The spelling of 1321350509 in words is "one billion, three hundred twenty-one million, three hundred fifty thousand, five hundred nine".