138928608 has 480 divisors, whose sum is σ = 546416640. Its totient is φ = 33592320.

The previous prime is 138928597. The next prime is 138928613. The reversal of 138928608 is 806829831.

138928608 is a `hidden beast` number, since 1 + 38 + 9 + 2 + 8 + 608 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 4481553 + ... + 4481583.

It is an arithmetic number, because the mean of its divisors is an integer number (1138368).

Almost surely, 2^138928608 is an apocalyptic number.

138928608 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138928608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (273208320).

138928608 is an abundant number, since it is smaller than the sum of its proper divisors (407488032).

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

138928608 is a wasteful number, since it uses less digits than its factorization.

138928608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92 (or 75 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 45.

The square root of 138928608 is about 11786.7980384836. The cubic root of 138928608 is about 517.9214462257.

It can be divided in two parts, 13892 and 8608, that added together give a square (22500 = 150²).

The spelling of 138928608 in words is "one hundred thirty-eight million, nine hundred twenty-eight thousand, six hundred eight".