31011161 has 2 divisors, whose sum is σ = 31011162. Its totient is φ = 31011160.

The previous prime is 31011131. The next prime is 31011163. The reversal of 31011161 is 16111013.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29767936 + 1243225 = 5456^2 + 1115^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31011161 is a prime.

Together with 31011163, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (31011163) 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, 15505580 + 15505581.

It is an arithmetic number, because the mean of its divisors is an integer number (15505581).

Almost surely, 2^31011161 is an apocalyptic number.

It is an amenable number.

31011161 is a deficient number, since it is larger than the sum of its proper divisors (1).

31011161 is an equidigital number, since it uses as much as digits as its factorization.

31011161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18, while the sum is 14.

The square root of 31011161 is about 5568.7665600203. The cubic root of 31011161 is about 314.1757606613.

Adding to 31011161 its reverse (16111013), we get a palindrome (47122174).

The spelling of 31011161 in words is "thirty-one million, eleven thousand, one hundred sixty-one".