320021 has 8 divisors (see below), whose sum is σ = 349440. Its totient is φ = 291312.

The previous prime is 320011. The next prime is 320027. The reversal of 320021 is 120023.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-320021 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 319990 and 320008.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 320021.

It is not an unprimeable number, because it can be changed into a prime (320027) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1220 + ... + 1458.

It is an arithmetic number, because the mean of its divisors is an integer number (43680).

2³²⁰⁰²¹ is an apocalyptic number.

It is an amenable number.

320021 is a deficient number, since it is larger than the sum of its proper divisors (29419).

320021 is a wasteful number, since it uses less digits than its factorization.

320021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 355.

The product of its (nonzero) digits is 12, while the sum is 8.

The square root of 320021 is about 565.7039861977. The cubic root of 320021 is about 68.4005340633.

Adding to 320021 its reverse (120023), we get a palindrome (440044).

The spelling of 320021 in words is "three hundred twenty thousand, twenty-one", and thus it is an iban number.