1321040389 has 2 divisors, whose sum is σ = 1321040390. Its totient is φ = 1321040388.

The previous prime is 1321040353. The next prime is 1321040431. The reversal of 1321040389 is 9830401231.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1101111489 + 219928900 = 33183^2 + 14830^2 .

It is a cyclic number.

It is not a de Polignac number, because 1321040389 - 2¹⁹ = 1320516101 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1321040389.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1321040689) 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, 660520194 + 660520195.

It is an arithmetic number, because the mean of its divisors is an integer number (660520195).

Almost surely, 2^1321040389 is an apocalyptic number.

It is an amenable number.

1321040389 is a deficient number, since it is larger than the sum of its proper divisors (1).

1321040389 is an equidigital number, since it uses as much as digits as its factorization.

1321040389 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 1321040389 is about 36346.1193114203. The cubic root of 1321040389 is about 1097.2494334091.

The spelling of 1321040389 in words is "one billion, three hundred twenty-one million, forty thousand, three hundred eighty-nine".