20121131313 has 12 divisors (see below), whose sum is σ = 29066513268. Its totient is φ = 13412861280.

The previous prime is 20121131293. The next prime is 20121131369. The reversal of 20121131313 is 31313112102.

20121131313 is a `hidden beast` number, since 201 + 21 + 131 + 313 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 8094061089 + 12027070224 = 89967^2 + 109668^2 .

It is not a de Polignac number, because 20121131313 - 2³² = 15826164017 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20121131383) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7983 + ... + 200763.

It is an arithmetic number, because the mean of its divisors is an integer number (2422209439).

Almost surely, 2^20121131313 is an apocalyptic number.

It is an amenable number.

20121131313 is a deficient number, since it is larger than the sum of its proper divisors (8945381955).

20121131313 is a wasteful number, since it uses less digits than its factorization.

20121131313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204384 (or 204381 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

Adding to 20121131313 its reverse (31313112102), we get a palindrome (51434243415).

The spelling of 20121131313 in words is "twenty billion, one hundred twenty-one million, one hundred thirty-one thousand, three hundred thirteen".