1001321 has 2 divisors, whose sum is σ = 1001322.
Its totient is φ = 1001320.
The previous prime is 1001311. The next prime is 1001323. The reversal of 1001321 is 1231001.
Adding to 1001321 its reverse (1231001), we get a palindrome (2232322).
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 714025 + 287296 = 845^2 + 536^2
It is an emirp because it is prime and its reverse (1231001) is a distict prime.
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-1001321 is a prime.
It is a Sophie Germain prime.
Together with 1001323, it forms a pair of twin primes.
It is a Chen prime.
It is a Curzon number.
It is a junction number, because it is equal to n+sod(n) for n = 1001299 and 1001308.
It is not a weakly prime, because it can be changed into another prime (1001323) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 500660 + 500661.
It is an arithmetic number, because the mean of its divisors is an integer number (500661).
21001321 is an apocalyptic number.
It is an amenable number.
1001321 is a deficient number, since it is larger than the sum of its proper divisors (1).
1001321 is an equidigital number, since it uses as much as digits as its factorization.
1001321 is an evil number, because the sum of its binary digits is even.
The product of its (nonzero) digits is 6, while the sum is 8.
The square root of 1001321 is about 1000.6602820138.
The cubic root of 1001321 is about 100.0440139582.
The spelling of 1001321 in words is "one million, one thousand, three hundred twenty-one".