320001021 has 12 divisors (see below), whose sum is σ = 486551520. Its totient is φ = 202105800.

The previous prime is 320001007. The next prime is 320001043. The reversal of 320001021 is 120100023.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-320001021 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 320000994 and 320001012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (320001221) 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 11 ways as a sum of consecutive naturals, for example, 935505 + ... + 935846.

It is an arithmetic number, because the mean of its divisors is an integer number (40545960).

Almost surely, 2^320001021 is an apocalyptic number.

It is an amenable number.

320001021 is a deficient number, since it is larger than the sum of its proper divisors (166550499).

320001021 is a wasteful number, since it uses less digits than its factorization.

320001021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1871376 (or 1871373 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

The square root of 320001021 is about 17888.5723577931. The cubic root of 320001021 is about 683.9911061222.

Adding to 320001021 its reverse (120100023), we get a palindrome (440101044).

The spelling of 320001021 in words is "three hundred twenty million, one thousand, twenty-one".