211221021121 has 4 divisors (see below), whose sum is σ = 230422932144. Its totient is φ = 192019110100.

The previous prime is 211221021083. The next prime is 211221021127. The reversal of 211221021121 is 121120122112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 211221021121 - 2¹³ = 211221012929 is a prime.

It is a super-2 number, since 2×211221021121² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211221021095 and 211221021104.

It is not an unprimeable number, because it can be changed into a prime (211221021127) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9600955495 + ... + 9600955516.

It is an arithmetic number, because the mean of its divisors is an integer number (57605733036).

Almost surely, 2^211221021121 is an apocalyptic number.

It is an amenable number.

211221021121 is a deficient number, since it is larger than the sum of its proper divisors (19201911023).

211221021121 is a wasteful number, since it uses less digits than its factorization.

211221021121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19201911022.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 211221021121 its reverse (121120122112), we get a palindrome (332341143233).

The spelling of 211221021121 in words is "two hundred eleven billion, two hundred twenty-one million, twenty-one thousand, one hundred twenty-one".