509138923 has 2 divisors, whose sum is σ = 509138924. Its totient is φ = 509138922.

The previous prime is 509138897. The next prime is 509138939. The reversal of 509138923 is 329831905.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 509138923 - 2¹³ = 509130731 is a prime.

It is not a weakly prime, because it can be changed into another prime (509138983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 254569461 + 254569462.

It is an arithmetic number, because the mean of its divisors is an integer number (254569462).

Almost surely, 2^509138923 is an apocalyptic number.

509138923 is a deficient number, since it is larger than the sum of its proper divisors (1).

509138923 is an equidigital number, since it uses as much as digits as its factorization.

509138923 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 58320, while the sum is 40.

The square root of 509138923 is about 22564.1069621645. The cubic root of 509138923 is about 798.5070714175.

The spelling of 509138923 in words is "five hundred nine million, one hundred thirty-eight thousand, nine hundred twenty-three".