212120100221 has 8 divisors (see below), whose sum is σ = 217415297400. Its totient is φ = 206830690560.

The previous prime is 212120100217. The next prime is 212120100233. The reversal of 212120100221 is 122001021212.

It can be written as a sum of positive squares in 4 ways, for example, as 27469416121 + 184650684100 = 165739^2 + 429710^2 .

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 212120100221 - 2² = 212120100217 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212120100196 and 212120100205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212120100211) 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, 1372616 + ... + 1519313.

It is an arithmetic number, because the mean of its divisors is an integer number (27176912175).

Almost surely, 2^212120100221 is an apocalyptic number.

It is an amenable number.

212120100221 is a deficient number, since it is larger than the sum of its proper divisors (5295197179).

212120100221 is a wasteful number, since it uses less digits than its factorization.

212120100221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2893759.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 212120100221 its reverse (122001021212), we get a palindrome (334121121433).

The spelling of 212120100221 in words is "two hundred twelve billion, one hundred twenty million, one hundred thousand, two hundred twenty-one".