1321839973 has 4 divisors (see below), whose sum is σ = 1323804748. Its totient is φ = 1319875200.

The previous prime is 1321839971. The next prime is 1321839997. The reversal of 1321839973 is 3799381231.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3799381231 = 1033 ⋅3678007.

It can be written as a sum of positive squares in 2 ways, for example, as 283518244 + 1038321729 = 16838^2 + 32223^2 .

It is a cyclic number.

It is not a de Polignac number, because 1321839973 - 2¹ = 1321839971 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321839971) 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 in 3 ways as a sum of consecutive naturals, for example, 981378 + ... + 982723.

It is an arithmetic number, because the mean of its divisors is an integer number (330951187).

Almost surely, 2^1321839973 is an apocalyptic number.

It is an amenable number.

1321839973 is a deficient number, since it is larger than the sum of its proper divisors (1964775).

1321839973 is an equidigital number, since it uses as much as digits as its factorization.

1321839973 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1964774.

The product of its digits is 244944, while the sum is 46.

The square root of 1321839973 is about 36357.1172262048. The cubic root of 1321839973 is about 1097.4707655623.

The spelling of 1321839973 in words is "one billion, three hundred twenty-one million, eight hundred thirty-nine thousand, nine hundred seventy-three".