201221202122 has 4 divisors (see below), whose sum is σ = 301831803186. Its totient is φ = 100610601060.

The previous prime is 201221202121. The next prime is 201221202211. The reversal of 201221202122 is 221202122102.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 199486396321 + 1734805801 = 446639^2 + 41651^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 201221202122.

It is not an unprimeable number, because it can be changed into a prime (201221202121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50305300529 + ... + 50305300532.

Almost surely, 2^201221202122 is an apocalyptic number.

201221202122 is a deficient number, since it is larger than the sum of its proper divisors (100610601064).

201221202122 is a wasteful number, since it uses less digits than its factorization.

201221202122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100610601063.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 201221202122 its reverse (221202122102), we get a palindrome (422423324224).

The spelling of 201221202122 in words is "two hundred one billion, two hundred twenty-one million, two hundred two thousand, one hundred twenty-two".