800320021 has 4 divisors (see below), whose sum is σ = 802177344. Its totient is φ = 798462700.

The previous prime is 800320019. The next prime is 800320049. The reversal of 800320021 is 120023008.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 800320021 - 2¹ = 800320019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 800319977 and 800320004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (800320051) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 928015 + ... + 928876.

It is an arithmetic number, because the mean of its divisors is an integer number (200544336).

Almost surely, 2^800320021 is an apocalyptic number.

It is an amenable number.

800320021 is a deficient number, since it is larger than the sum of its proper divisors (1857323).

800320021 is a wasteful number, since it uses less digits than its factorization.

800320021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1857322.

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 800320021 is about 28289.9279072959. The cubic root of 800320021 is about 928.4415340456.

Adding to 800320021 its reverse (120023008), we get a palindrome (920343029).

The spelling of 800320021 in words is "eight hundred million, three hundred twenty thousand, twenty-one".