212121010100221 has 4 divisors (see below), whose sum is σ = 212121069420832. Its totient is φ = 212120950779612.

The previous prime is 212121010100213. The next prime is 212121010100273. The reversal of 212121010100221 is 122001010121212.

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 212121010100221 - 2³ = 212121010100213 is a prime.

It is a super-3 number, since 3×212121010100221³ (a number of 44 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212121010100195 and 212121010100204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212121010100201) 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, 23927151 + ... + 31571356.

It is an arithmetic number, because the mean of its divisors is an integer number (53030267355208).

Almost surely, 2^{212121010100221} is an apocalyptic number.

It is an amenable number.

212121010100221 is a deficient number, since it is larger than the sum of its proper divisors (59320611).

212121010100221 is an equidigital number, since it uses as much as digits as its factorization.

212121010100221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59320610.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 212121010100221 its reverse (122001010121212), we get a palindrome (334122020221433).

The spelling of 212121010100221 in words is "two hundred twelve trillion, one hundred twenty-one billion, ten million, one hundred thousand, two hundred twenty-one".