320100021 has 48 divisors (see below), whose sum is σ = 504092160. Its totient is φ = 194987520.

The previous prime is 320099977. The next prime is 320100031. The reversal of 320100021 is 120001023.

It is a happy number.

It is not a de Polignac number, because 320100021 - 2¹³ = 320091829 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 = 320099976 and 320100012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (320100031) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 857991 + ... + 858363.

It is an arithmetic number, because the mean of its divisors is an integer number (10501920).

Almost surely, 2^320100021 is an apocalyptic number.

It is an amenable number.

320100021 is a deficient number, since it is larger than the sum of its proper divisors (183992139).

320100021 is a wasteful number, since it uses less digits than its factorization.

320100021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 546 (or 543 counting only the distinct ones).

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

The square root of 320100021 is about 17891.3392735144. The cubic root of 320100021 is about 684.0616352071.

Adding to 320100021 its reverse (120001023), we get a palindrome (440101044).

The spelling of 320100021 in words is "three hundred twenty million, one hundred thousand, twenty-one".