31958009 has 2 divisors, whose sum is σ = 31958010. Its totient is φ = 31958008.

The previous prime is 31957997. The next prime is 31958021. The reversal of 31958009 is 90085913.

It is a balanced prime because it is at equal distance from previous prime (31957997) and next prime (31958021).

It can be written as a sum of positive squares in only one way, i.e., 31956409 + 1600 = 5653^2 + 40^2 .

It is an emirp because it is prime and its reverse (90085913) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31958009 - 2¹⁶ = 31892473 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31958009.

It is not a weakly prime, because it can be changed into another prime (31958039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15979004 + 15979005.

It is an arithmetic number, because the mean of its divisors is an integer number (15979005).

Almost surely, 2^31958009 is an apocalyptic number.

It is an amenable number.

31958009 is a deficient number, since it is larger than the sum of its proper divisors (1).

31958009 is an equidigital number, since it uses as much as digits as its factorization.

31958009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9720, while the sum is 35.

The square root of 31958009 is about 5653.1415160068. The cubic root of 31958009 is about 317.3412817794.

The spelling of 31958009 in words is "thirty-one million, nine hundred fifty-eight thousand, nine".