31102121 has 2 divisors, whose sum is σ = 31102122. Its totient is φ = 31102120.

The previous prime is 31102087. The next prime is 31102133. The reversal of 31102121 is 12120113.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20830096 + 10272025 = 4564^2 + 3205^2 .

It is a cyclic number.

It is not a de Polignac number, because 31102121 - 2¹⁰ = 31101097 is a prime.

It is not a weakly prime, because it can be changed into another prime (31101121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15551060 + 15551061.

It is an arithmetic number, because the mean of its divisors is an integer number (15551061).

Almost surely, 2^31102121 is an apocalyptic number.

It is an amenable number.

31102121 is a deficient number, since it is larger than the sum of its proper divisors (1).

31102121 is an equidigital number, since it uses as much as digits as its factorization.

31102121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12, while the sum is 11.

The square root of 31102121 is about 5576.9275591494. The cubic root of 31102121 is about 314.4826343932.

Adding to 31102121 its reverse (12120113), we get a palindrome (43222234).

The spelling of 31102121 in words is "thirty-one million, one hundred two thousand, one hundred twenty-one".