211011211221 has 8 divisors (see below), whose sum is σ = 285547509984. Its totient is φ = 138574526640.

The previous prime is 211011211217. The next prime is 211011211223. The reversal of 211011211221 is 122112110112.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 211011211221 - 2² = 211011211217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 211011211221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211011211223) 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, 524903310 + ... + 524903711.

It is an arithmetic number, because the mean of its divisors is an integer number (35693438748).

Almost surely, 2^211011211221 is an apocalyptic number.

It is an amenable number.

211011211221 is a deficient number, since it is larger than the sum of its proper divisors (74536298763).

211011211221 is a wasteful number, since it uses less digits than its factorization.

211011211221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1049807091.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 211011211221 its reverse (122112110112), we get a palindrome (333123321333).

The spelling of 211011211221 in words is "two hundred eleven billion, eleven million, two hundred eleven thousand, two hundred twenty-one".