212030221 has 4 divisors (see below), whose sum is σ = 228340252. Its totient is φ = 195720192.

The previous prime is 212030201. The next prime is 212030257. The reversal of 212030221 is 122030212.

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 88153321 + 123876900 = 9389^2 + 11130^2 .

It is a cyclic number.

It is not a de Polignac number, because 212030221 - 2¹⁹ = 211505933 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13), and also a Moran number because the ratio is a prime number: 16310017 = 212030221 / (2 + 1 + 2 + 0 + 3 + 0 + 2 + 2 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212030201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8154996 + ... + 8155021.

It is an arithmetic number, because the mean of its divisors is an integer number (57085063).

Almost surely, 2^212030221 is an apocalyptic number.

It is an amenable number.

212030221 is a deficient number, since it is larger than the sum of its proper divisors (16310031).

212030221 is a wasteful number, since it uses less digits than its factorization.

212030221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16310030.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 212030221 is about 14561.2575349796. The cubic root of 212030221 is about 596.3015277179.

Adding to 212030221 its reverse (122030212), we get a palindrome (334060433).

Subtracting from 212030221 its reverse (122030212), we obtain a palindrome (90000009).

The spelling of 212030221 in words is "two hundred twelve million, thirty thousand, two hundred twenty-one".