211220201210221 has 6 divisors (see below), whose sum is σ = 245705132020110. Its totient is φ = 181045886751576.

The previous prime is 211220201210191. The next prime is 211220201210261. The reversal of 211220201210221 is 122012102022112.

It can be written as a sum of positive squares in only one way, i.e., 132696322933321 + 78523878276900 = 11519389^2 + 8861370^2 .

It is not a de Polignac number, because 211220201210221 - 2⁹ = 211220201209709 is a prime.

It is a super-2 number, since 2×211220201210221² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211220201210261) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2155308175566 + ... + 2155308175663.

It is an arithmetic number, because the mean of its divisors is an integer number (40950855336685).

Almost surely, 2^{211220201210221} is an apocalyptic number.

It is an amenable number.

211220201210221 is a deficient number, since it is larger than the sum of its proper divisors (34484930809889).

211220201210221 is an equidigital number, since it uses as much as digits as its factorization.

211220201210221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4310616351243 (or 4310616351236 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 211220201210221 its reverse (122012102022112), we get a palindrome (333232303232333).

The spelling of 211220201210221 in words is "two hundred eleven trillion, two hundred twenty billion, two hundred one million, two hundred ten thousand, two hundred twenty-one".