200021221 has 4 divisors (see below), whose sum is σ = 200414700. Its totient is φ = 199627744.

The previous prime is 200021219. The next prime is 200021243. The reversal of 200021221 is 122120002.

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 139570596 + 60450625 = 11814^2 + 7775^2 .

It is a cyclic number.

It is not a de Polignac number, because 200021221 - 2¹ = 200021219 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 200021198 and 200021207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (200021281) 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, 195976 + ... + 196993.

It is an arithmetic number, because the mean of its divisors is an integer number (50103675).

Almost surely, 2^200021221 is an apocalyptic number.

It is an amenable number.

200021221 is a deficient number, since it is larger than the sum of its proper divisors (393479).

200021221 is an equidigital number, since it uses as much as digits as its factorization.

200021221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 393478.

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 200021221 is about 14142.8858794802. The cubic root of 200021221 is about 584.8242304379.

Adding to 200021221 its reverse (122120002), we get a palindrome (322141223).

It can be divided in two parts, 20002 and 1221, that multiplied together give a palindrome (24422442).

The spelling of 200021221 in words is "two hundred million, twenty-one thousand, two hundred twenty-one".