31128193 has 2 divisors, whose sum is σ = 31128194. Its totient is φ = 31128192.

The previous prime is 31128191. The next prime is 31128203. The reversal of 31128193 is 39182113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18045504 + 13082689 = 4248^2 + 3617^2 .

It is an emirp because it is prime and its reverse (39182113) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31128193 - 2¹ = 31128191 is a prime.

Together with 31128191, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (31128191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15564096 + 15564097.

It is an arithmetic number, because the mean of its divisors is an integer number (15564097).

Almost surely, 2^31128193 is an apocalyptic number.

It is an amenable number.

31128193 is a deficient number, since it is larger than the sum of its proper divisors (1).

31128193 is an equidigital number, since it uses as much as digits as its factorization.

31128193 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1296, while the sum is 28.

The square root of 31128193 is about 5579.2645572692. The cubic root of 31128193 is about 314.5704837210.

The spelling of 31128193 in words is "thirty-one million, one hundred twenty-eight thousand, one hundred ninety-three".