138509268 has 48 divisors (see below), whose sum is σ = 343030464. Its totient is φ = 43348480.

The previous prime is 138509257. The next prime is 138509291. The reversal of 138509268 is 862905831.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 167071 + ... + 167897.

It is an arithmetic number, because the mean of its divisors is an integer number (7146468).

Almost surely, 2^138509268 is an apocalyptic number.

It is an amenable number.

138509268 is an abundant number, since it is smaller than the sum of its proper divisors (204521196).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

138509268 is a wasteful number, since it uses less digits than its factorization.

138509268 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1672 (or 1670 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 42.

The square root of 138509268 is about 11768.9960489415. The cubic root of 138509268 is about 517.3998256474.

The spelling of 138509268 in words is "one hundred thirty-eight million, five hundred nine thousand, two hundred sixty-eight".