20111131121 has 12 divisors (see below), whose sum is σ = 21372578640. Its totient is φ = 18920281920.

The previous prime is 20111131063. The next prime is 20111131123. The reversal of 20111131121 is 12113111102.

It is not a de Polignac number, because 20111131121 - 2¹⁸ = 20110868977 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20111131096 and 20111131105.

It is not an unprimeable number, because it can be changed into a prime (20111131123) 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 11 ways as a sum of consecutive naturals, for example, 755366 + ... + 781536.

It is an arithmetic number, because the mean of its divisors is an integer number (1781048220).

Almost surely, 2^20111131121 is an apocalyptic number.

It is an amenable number.

20111131121 is a deficient number, since it is larger than the sum of its proper divisors (1261447519).

20111131121 is a wasteful number, since it uses less digits than its factorization.

20111131121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28864 (or 28847 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 14.

Adding to 20111131121 its reverse (12113111102), we get a palindrome (32224242223).

It can be divided in two parts, 201111 and 31121, that added together give a palindrome (232232).

The spelling of 20111131121 in words is "twenty billion, one hundred eleven million, one hundred thirty-one thousand, one hundred twenty-one".