20121031121 has 2 divisors, whose sum is σ = 20121031122. Its totient is φ = 20121031120.

The previous prime is 20121031093. The next prime is 20121031123. The reversal of 20121031121 is 12113012102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12693176896 + 7427854225 = 112664^2 + 86185^2 .

It is a cyclic number.

It is not a de Polignac number, because 20121031121 - 2⁶ = 20121031057 is a prime.

Together with 20121031123, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 20121031096 and 20121031105.

It is not a weakly prime, because it can be changed into another prime (20121031123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10060515560 + 10060515561.

It is an arithmetic number, because the mean of its divisors is an integer number (10060515561).

Almost surely, 2^20121031121 is an apocalyptic number.

It is an amenable number.

20121031121 is a deficient number, since it is larger than the sum of its proper divisors (1).

20121031121 is an equidigital number, since it uses as much as digits as its factorization.

20121031121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 20121031121 its reverse (12113012102), we get a palindrome (32234043223).

The spelling of 20121031121 in words is "twenty billion, one hundred twenty-one million, thirty-one thousand, one hundred twenty-one".