138013440 has 144 divisors (see below), whose sum is σ = 445820928. Its totient is φ = 36384768.

The previous prime is 138013439. The next prime is 138013451. The reversal of 138013440 is 44310831.

138013440 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 138013440.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 487539 + ... + 487821.

Almost surely, 2^138013440 is an apocalyptic number.

138013440 is a gapful number since it is divisible by the number (10) 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 138013440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (222910464).

138013440 is an abundant number, since it is smaller than the sum of its proper divisors (307807488).

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

138013440 is a wasteful number, since it uses less digits than its factorization.

138013440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 434 (or 420 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 138013440 is about 11747.9121549320. The cubic root of 138013440 is about 516.7817008285.

The spelling of 138013440 in words is "one hundred thirty-eight million, thirteen thousand, four hundred forty".