212131100221 has 8 divisors (see below), whose sum is σ = 224614305720. Its totient is φ = 199648439808.

The previous prime is 212131100213. The next prime is 212131100239. The reversal of 212131100221 is 122001131212.

It can be written as a sum of positive squares in 4 ways, for example, as 94670674596 + 117460425625 = 307686^2 + 342725^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 212131100221 - 2³ = 212131100213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212131100195 and 212131100204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212131100201) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 882745 + ... + 1097041.

It is an arithmetic number, because the mean of its divisors is an integer number (28076788215).

Almost surely, 2^212131100221 is an apocalyptic number.

It is an amenable number.

212131100221 is a deficient number, since it is larger than the sum of its proper divisors (12483205499).

212131100221 is a wasteful number, since it uses less digits than its factorization.

212131100221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272543.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 212131100221 its reverse (122001131212), we get a palindrome (334132231433).

The spelling of 212131100221 in words is "two hundred twelve billion, one hundred thirty-one million, one hundred thousand, two hundred twenty-one".