31129243 has 2 divisors, whose sum is σ = 31129244. Its totient is φ = 31129242.

The previous prime is 31129237. The next prime is 31129253. The reversal of 31129243 is 34292113.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31129243 - 2⁵ = 31129211 is a prime.

It is not a weakly prime, because it can be changed into another prime (31129213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15564621 + 15564622.

It is an arithmetic number, because the mean of its divisors is an integer number (15564622).

Almost surely, 2^31129243 is an apocalyptic number.

31129243 is a deficient number, since it is larger than the sum of its proper divisors (1).

31129243 is an equidigital number, since it uses as much as digits as its factorization.

31129243 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1296, while the sum is 25.

The square root of 31129243 is about 5579.3586548993. The cubic root of 31129243 is about 314.5740206571.

The spelling of 31129243 in words is "thirty-one million, one hundred twenty-nine thousand, two hundred forty-three".