20121122121 has 32 divisors (see below), whose sum is σ = 27503870592. Its totient is φ = 13080476160.

The previous prime is 20121122117. The next prime is 20121122149. The reversal of 20121122121 is 12122112102.

It is not a de Polignac number, because 20121122121 - 2² = 20121122117 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20121122121.

It is not an unprimeable number, because it can be changed into a prime (20121122111) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 19477821 + ... + 19478853.

It is an arithmetic number, because the mean of its divisors is an integer number (859495956).

Almost surely, 2^20121122121 is an apocalyptic number.

It is an amenable number.

20121122121 is a deficient number, since it is larger than the sum of its proper divisors (7382748471).

20121122121 is a wasteful number, since it uses less digits than its factorization.

20121122121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1913.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 20121122121 its reverse (12122112102), we get a palindrome (32243234223).

The spelling of 20121122121 in words is "twenty billion, one hundred twenty-one million, one hundred twenty-two thousand, one hundred twenty-one".