31133131 has 2 divisors, whose sum is σ = 31133132. Its totient is φ = 31133130.

The previous prime is 31133087. The next prime is 31133147. The reversal of 31133131 is 13133113.

It is an a-pointer prime, because the next prime (31133147) can be obtained adding 31133131 to its sum of digits (16).

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 31133131 - 2¹⁹ = 30608843 is a prime.

It is a super-2 number, since 2×31133131² = 1938543691726322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31133231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15566565 + 15566566.

It is an arithmetic number, because the mean of its divisors is an integer number (15566566).

Almost surely, 2^31133131 is an apocalyptic number.

31133131 is a deficient number, since it is larger than the sum of its proper divisors (1).

31133131 is an equidigital number, since it uses as much as digits as its factorization.

31133131 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 81, while the sum is 16.

The square root of 31133131 is about 5579.7070711642. The cubic root of 31133131 is about 314.5871167340.

Adding to 31133131 its reverse (13133113), we get a palindrome (44266244).

The spelling of 31133131 in words is "thirty-one million, one hundred thirty-three thousand, one hundred thirty-one".