809438137 has 2 divisors, whose sum is σ = 809438138. Its totient is φ = 809438136.

The previous prime is 809438129. The next prime is 809438173. The reversal of 809438137 is 731834908.

It is a happy number.

Together with next prime (809438173) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 753173136 + 56265001 = 27444^2 + 7501^2 .

It is a cyclic number.

It is not a de Polignac number, because 809438137 - 2³ = 809438129 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 809438093 and 809438102.

It is not a weakly prime, because it can be changed into another prime (809438107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 404719068 + 404719069.

It is an arithmetic number, because the mean of its divisors is an integer number (404719069).

Almost surely, 2^809438137 is an apocalyptic number.

It is an amenable number.

809438137 is a deficient number, since it is larger than the sum of its proper divisors (1).

809438137 is an equidigital number, since it uses as much as digits as its factorization.

809438137 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 145152, while the sum is 43.

The square root of 809438137 is about 28450.6263024208. The cubic root of 809438137 is about 931.9541662547.

The spelling of 809438137 in words is "eight hundred nine million, four hundred thirty-eight thousand, one hundred thirty-seven".