8020021 has 4 divisors (see below), whose sum is σ = 8048844. Its totient is φ = 7991200.

The previous prime is 8020007. The next prime is 8020027. The reversal of 8020021 is 1200208.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3651921 + 4368100 = 1911^2 + 2090^2 .

It is a cyclic number.

It is not a de Polignac number, because 8020021 - 2⁵ = 8019989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 8019983 and 8020010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8020027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13990 + ... + 14551.

It is an arithmetic number, because the mean of its divisors is an integer number (2012211).

Almost surely, 2^8020021 is an apocalyptic number.

It is an amenable number.

8020021 is a deficient number, since it is larger than the sum of its proper divisors (28823).

8020021 is a wasteful number, since it uses less digits than its factorization.

8020021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28822.

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 8020021 is about 2831.9641593777. The cubic root of 8020021 is about 200.1667026791.

Adding to 8020021 its reverse (1200208), we get a palindrome (9220229).

The spelling of 8020021 in words is "eight million, twenty thousand, twenty-one".