212121102011221 has 8 divisors (see below), whose sum is σ = 241875645732504. Its totient is φ = 184286206272000.

The previous prime is 212121102011219. The next prime is 212121102011249. The reversal of 212121102011221 is 122110201121212.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 20064722500 + 212101037288721 = 141650^2 + 14563689^2 .

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 212121102011221 - 2¹ = 212121102011219 is a prime.

It is a super-3 number, since 3×212121102011221³ (a number of 44 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212121108011221) 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, 479911995280 + ... + 479911995721.

It is an arithmetic number, because the mean of its divisors is an integer number (30234455716563).

Almost surely, 2^{212121102011221} is an apocalyptic number.

It is an amenable number.

212121102011221 is a deficient number, since it is larger than the sum of its proper divisors (29754543721283).

212121102011221 is a wasteful number, since it uses less digits than its factorization.

212121102011221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 959823991031.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 212121102011221 its reverse (122110201121212), we get a palindrome (334231303132433).

The spelling of 212121102011221 in words is "two hundred twelve trillion, one hundred twenty-one billion, one hundred two million, eleven thousand, two hundred twenty-one".