138959540 has 24 divisors (see below), whose sum is σ = 307174560. Its totient is φ = 52658208.

The previous prime is 138959539. The next prime is 138959549. The reversal of 138959540 is 45959831.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 138959491 and 138959500.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138959549) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 182462 + ... + 183221.

It is an arithmetic number, because the mean of its divisors is an integer number (12798940).

Almost surely, 2^138959540 is an apocalyptic number.

138959540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138959540 is an abundant number, since it is smaller than the sum of its proper divisors (168215020).

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

138959540 is a wasteful number, since it uses less digits than its factorization.

138959540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 365711 (or 365709 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 44.

The square root of 138959540 is about 11788.1101114640. The cubic root of 138959540 is about 517.9598812119.

The spelling of 138959540 in words is "one hundred thirty-eight million, nine hundred fifty-nine thousand, five hundred forty".