138930 has 32 divisors (see below), whose sum is σ = 364608. Its totient is φ = 33600.

The previous prime is 138923. The next prime is 138937. The reversal of 138930 is 39831.

138930 = T₅₅ + T₅₆ + ... + T₉₉.

138930 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (138923) and next prime (138937).

It is a nialpdrome in base 11.

It is a self number, because there is not a number n which added to its sum of digits gives 138930.

It is not an unprimeable number, because it can be changed into a prime (138937) by changing a digit.

138930 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 120 + ... + 540.

It is an arithmetic number, because the mean of its divisors is an integer number (11394).

2¹³⁸⁹³⁰ is an apocalyptic number.

138930 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 138930, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (182304).

138930 is an abundant number, since it is smaller than the sum of its proper divisors (225678).

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

138930 is a wasteful number, since it uses less digits than its factorization.

138930 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 442.

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 138930 is about 372.7331485124. The cubic root of 138930 is about 51.7923175997.

Subtracting from 138930 its reverse (39831), we obtain a palindrome (99099).

The spelling of 138930 in words is "one hundred thirty-eight thousand, nine hundred thirty".