1212210201221 has 4 divisors (see below), whose sum is σ = 1212221061792.
Its totient is φ = 1212199340652.
The previous prime is 1212210201203. The next prime is 1212210201253. The reversal of 1212210201221 is 1221020122121.
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 1212210201221 - 210 = 1212210200197 is a prime.
It is a Duffinian number.
It is a self number, because there is not a number n which added to its sum of digits gives 1212210201221.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (1212210201281) 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, 5261105 + ... + 5486678.
It is an arithmetic number, because the mean of its divisors is an integer number (303055265448).
Almost surely, 21212210201221 is an apocalyptic number.
It is an amenable number.
1212210201221 is a deficient number, since it is larger than the sum of its proper divisors (10860571).
1212210201221 is a wasteful number, since it uses less digits than its factorization.
1212210201221 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 10860570.
The product of its (nonzero) digits is 64, while the sum is 17.
Adding to 1212210201221 its reverse (1221020122121), we get a palindrome (2433230323342).
The spelling of 1212210201221 in words is "one trillion, two hundred twelve billion, two hundred ten million, two hundred one thousand, two hundred twenty-one".