212021121211 has 4 divisors (see below), whose sum is σ = 212054787000.
Its totient is φ = 211987455424.
The previous prime is 212021121199. The next prime is 212021121227. The reversal of 212021121211 is 112121120212.
It is a semiprime because it is the product of two primes.
It is a cyclic number.
It is not a de Polignac number, because 212021121211 - 29 = 212021120699 is a prime.
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (212021121281) 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, 16823446 + ... + 16836043.
It is an arithmetic number, because the mean of its divisors is an integer number (53013696750).
Almost surely, 2212021121211 is an apocalyptic number.
212021121211 is a deficient number, since it is larger than the sum of its proper divisors (33665789).
212021121211 is an equidigital number, since it uses as much as digits as its factorization.
212021121211 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 33665788.
The product of its (nonzero) digits is 32, while the sum is 16.
Adding to 212021121211 its reverse (112121120212), we get a palindrome (324142241423).
Subtracting from 212021121211 its reverse (112121120212), we obtain a palindrome (99900000999).
The spelling of 212021121211 in words is "two hundred twelve billion, twenty-one million, one hundred twenty-one thousand, two hundred eleven".