211221101 has 24 divisors (see below), whose sum is σ = 265768704. Its totient is φ = 164324160.

The previous prime is 211221091. The next prime is 211221169. The reversal of 211221101 is 101122112.

It is not a de Polignac number, because 211221101 - 2⁶ = 211221037 is a prime.

It is a super-2 number, since 2×211221101² = 89228707015304402, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211221301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 70700 + ... + 73626.

It is an arithmetic number, because the mean of its divisors is an integer number (11073696).

Almost surely, 2^211221101 is an apocalyptic number.

It is an amenable number.

211221101 is a deficient number, since it is larger than the sum of its proper divisors (54547603).

211221101 is a wasteful number, since it uses less digits than its factorization.

211221101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3021 (or 3008 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

The square root of 211221101 is about 14533.4476639234. The cubic root of 211221101 is about 595.5420534036.

Adding to 211221101 its reverse (101122112), we get a palindrome (312343213).

The spelling of 211221101 in words is "two hundred eleven million, two hundred twenty-one thousand, one hundred one".