211220210111221 has 8 divisors (see below), whose sum is σ = 215715098559744. Its totient is φ = 206725356722160.

The previous prime is 211220210111203. The next prime is 211220210111329. The reversal of 211220210111221 is 122111012022112.

It is a happy number.

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 211220210111221 - 2²⁹ = 211219673240309 is a prime.

It is a super-2 number, since 2×211220210111221² (a number of 29 digits) contains 22 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 (211220210111201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3596131 + ... + 20865583.

It is an arithmetic number, because the mean of its divisors is an integer number (26964387319968).

Almost surely, 2^{211220210111221} is an apocalyptic number.

It is an amenable number.

211220210111221 is a deficient number, since it is larger than the sum of its proper divisors (4494888448523).

211220210111221 is a wasteful number, since it uses less digits than its factorization.

211220210111221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17529731.

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

Adding to 211220210111221 its reverse (122111012022112), we get a palindrome (333331222133333).

The spelling of 211220210111221 in words is "two hundred eleven trillion, two hundred twenty billion, two hundred ten million, one hundred eleven thousand, two hundred twenty-one".