138598509 has 12 divisors (see below), whose sum is σ = 214969344. Its totient is φ = 79199064.

The previous prime is 138598507. The next prime is 138598513. The reversal of 138598509 is 905895831.

It is not a de Polignac number, because 138598509 - 2¹ = 138598507 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138598507) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 471277 + ... + 471570.

It is an arithmetic number, because the mean of its divisors is an integer number (17914112).

Almost surely, 2^138598509 is an apocalyptic number.

It is an amenable number.

138598509 is a deficient number, since it is larger than the sum of its proper divisors (76370835).

138598509 is an equidigital number, since it uses as much as digits as its factorization.

138598509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 942864 (or 942857 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 48.

The square root of 138598509 is about 11772.7867983753. The cubic root of 138598509 is about 517.5109213780.

The spelling of 138598509 in words is "one hundred thirty-eight million, five hundred ninety-eight thousand, five hundred nine".