20121220111211 has 4 divisors (see below), whose sum is σ = 20180926996152. Its totient is φ = 20061513226272.

The previous prime is 20121220111199. The next prime is 20121220111241. The reversal of 20121220111211 is 11211102212102.

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 20121220111211 - 2²⁶ = 20121153002347 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20121220111211.

It is not an unprimeable number, because it can be changed into a prime (20121220111241) 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, 29853441965 + ... + 29853442638.

It is an arithmetic number, because the mean of its divisors is an integer number (5045231749038).

Almost surely, 2^{20121220111211} is an apocalyptic number.

20121220111211 is a deficient number, since it is larger than the sum of its proper divisors (59706884941).

20121220111211 is an equidigital number, since it uses as much as digits as its factorization.

20121220111211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59706884940.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 20121220111211 its reverse (11211102212102), we get a palindrome (31332322323313).

The spelling of 20121220111211 in words is "twenty trillion, one hundred twenty-one billion, two hundred twenty million, one hundred eleven thousand, two hundred eleven".