3131020121 has 2 divisors, whose sum is σ = 3131020122. Its totient is φ = 3131020120.

The previous prime is 3131020117. The next prime is 3131020141. The reversal of 3131020121 is 1210201313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1597201225 + 1533818896 = 39965^2 + 39164^2 .

It is a cyclic number.

It is not a de Polignac number, because 3131020121 - 2² = 3131020117 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 3131020096 and 3131020105.

It is not a weakly prime, because it can be changed into another prime (3131020141) 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 as a sum of consecutive naturals, namely, 1565510060 + 1565510061.

It is an arithmetic number, because the mean of its divisors is an integer number (1565510061).

Almost surely, 2^3131020121 is an apocalyptic number.

It is an amenable number.

3131020121 is a deficient number, since it is larger than the sum of its proper divisors (1).

3131020121 is an equidigital number, since it uses as much as digits as its factorization.

3131020121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 3131020121 is about 55955.5191290368. The cubic root of 3131020121 is about 1462.9470903870.

Adding to 3131020121 its reverse (1210201313), we get a palindrome (4341221434).

The spelling of 3131020121 in words is "three billion, one hundred thirty-one million, twenty thousand, one hundred twenty-one".