1321439969 has 2 divisors, whose sum is σ = 1321439970. Its totient is φ = 1321439968.

The previous prime is 1321439947. The next prime is 1321440023. The reversal of 1321439969 is 9699341231.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 725494225 + 595945744 = 26935^2 + 24412^2 .

It is an emirp because it is prime and its reverse (9699341231) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1321439969 - 2²⁰ = 1320391393 is a prime.

It is a super-2 number, since 2×1321439969² = 3492407183341441922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1321439269) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660719984 + 660719985.

It is an arithmetic number, because the mean of its divisors is an integer number (660719985).

Almost surely, 2^1321439969 is an apocalyptic number.

It is an amenable number.

1321439969 is a deficient number, since it is larger than the sum of its proper divisors (1).

1321439969 is an equidigital number, since it uses as much as digits as its factorization.

1321439969 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 314928, while the sum is 47.

The square root of 1321439969 is about 36351.6157687660. The cubic root of 1321439969 is about 1097.3600519625.

The spelling of 1321439969 in words is "one billion, three hundred twenty-one million, four hundred thirty-nine thousand, nine hundred sixty-nine".