320170021 has 2 divisors, whose sum is σ = 320170022. Its totient is φ = 320170020.

The previous prime is 320170009. The next prime is 320170033. The reversal of 320170021 is 120071023.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (320170009) and next prime (320170033).

It can be written as a sum of positive squares in only one way, i.e., 230128900 + 90041121 = 15170^2 + 9489^2 .

It is a cyclic number.

It is not a de Polignac number, because 320170021 - 2⁵ = 320169989 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 320169977 and 320170004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (320170091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160085010 + 160085011.

It is an arithmetic number, because the mean of its divisors is an integer number (160085011).

Almost surely, 2^320170021 is an apocalyptic number.

It is an amenable number.

320170021 is a deficient number, since it is larger than the sum of its proper divisors (1).

320170021 is an equidigital number, since it uses as much as digits as its factorization.

320170021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 84, while the sum is 16.

The square root of 320170021 is about 17893.2954203523. The cubic root of 320170021 is about 684.1114954813. Note that the first 3 decimals are identical.

The spelling of 320170021 in words is "three hundred twenty million, one hundred seventy thousand, twenty-one".