920021 has 2 divisors, whose sum is σ = 920022. Its totient is φ = 920020.

The previous prime is 920011. The next prime is 920039. The reversal of 920021 is 120029.

920021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 874225 + 45796 = 935^2 + 214^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-920021 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 919978 and 920005.

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 920021.

It is not a weakly prime, because it can be changed into another prime (920011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 460010 + 460011.

It is an arithmetic number, because the mean of its divisors is an integer number (460011).

2⁹²⁰⁰²¹ is an apocalyptic number.

It is an amenable number.

920021 is a deficient number, since it is larger than the sum of its proper divisors (1).

920021 is an equidigital number, since it uses as much as digits as its factorization.

920021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 920021 is about 959.1772516068. The cubic root of 920021 is about 97.2596226295.

The spelling of 920021 in words is "nine hundred twenty thousand, twenty-one".