20121211201121 has 4 divisors (see below), whose sum is σ = 20121230039700. Its totient is φ = 20121192362544.

The previous prime is 20121211201111. The next prime is 20121211201277. The reversal of 20121211201121 is 12110211212102.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8704482512896 + 11416728688225 = 2950336^2 + 3378865^2 .

It is a cyclic number.

It is not a de Polignac number, because 20121211201121 - 2⁶ = 20121211201057 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 20121211201121.

It is not an unprimeable number, because it can be changed into a prime (20121211201111) 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, 7714286 + ... + 9987623.

It is an arithmetic number, because the mean of its divisors is an integer number (5030307509925).

Almost surely, 2^{20121211201121} is an apocalyptic number.

It is an amenable number.

20121211201121 is a deficient number, since it is larger than the sum of its proper divisors (18838579).

20121211201121 is a wasteful number, since it uses less digits than its factorization.

20121211201121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18838578.

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

Adding to 20121211201121 its reverse (12110211212102), we get a palindrome (32231422413223).

The spelling of 20121211201121 in words is "twenty trillion, one hundred twenty-one billion, two hundred eleven million, two hundred one thousand, one hundred twenty-one".