211221011010121 has 4 divisors (see below), whose sum is σ = 241395441154432. Its totient is φ = 181046580865812.

The previous prime is 211221011010103. The next prime is 211221011010133. The reversal of 211221011010121 is 121010110122112.

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 211221011010121 - 2¹⁹ = 211221010485833 is a prime.

It is a super-2 number, since 2×211221011010121² (a number of 29 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 = 211221011010095 and 211221011010104.

It is not an unprimeable number, because it can be changed into a prime (211221011010181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15087215072145 + ... + 15087215072158.

It is an arithmetic number, because the mean of its divisors is an integer number (60348860288608).

Almost surely, 2^{211221011010121} is an apocalyptic number.

It is an amenable number.

211221011010121 is a deficient number, since it is larger than the sum of its proper divisors (30174430144311).

211221011010121 is an equidigital number, since it uses as much as digits as its factorization.

211221011010121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30174430144310.

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

Adding to 211221011010121 its reverse (121010110122112), we get a palindrome (332231121132233).

The spelling of 211221011010121 in words is "two hundred eleven trillion, two hundred twenty-one billion, eleven million, ten thousand, one hundred twenty-one".