31130161 has 2 divisors, whose sum is σ = 31130162. Its totient is φ = 31130160.

The previous prime is 31130149. The next prime is 31130171. The reversal of 31130161 is 16103113.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25441936 + 5688225 = 5044^2 + 2385^2 .

It is a cyclic number.

It is not a de Polignac number, because 31130161 - 2²¹ = 29033009 is a prime.

It is not a weakly prime, because it can be changed into another prime (31130101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15565080 + 15565081.

It is an arithmetic number, because the mean of its divisors is an integer number (15565081).

Almost surely, 2^31130161 is an apocalyptic number.

It is an amenable number.

31130161 is a deficient number, since it is larger than the sum of its proper divisors (1).

31130161 is an equidigital number, since it uses as much as digits as its factorization.

31130161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 54, while the sum is 16.

The square root of 31130161 is about 5579.4409218129. The cubic root of 31130161 is about 314.5771128847.

Adding to 31130161 its reverse (16103113), we get a palindrome (47233274).

The spelling of 31130161 in words is "thirty-one million, one hundred thirty thousand, one hundred sixty-one".