138345520 has 40 divisors (see below), whose sum is σ = 323483760. Its totient is φ = 55023360.

The previous prime is 138345503. The next prime is 138345527. The reversal of 138345520 is 25543831.

138345520 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (138345527) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9490 + ... + 19150.

It is an arithmetic number, because the mean of its divisors is an integer number (8087094).

Almost surely, 2^138345520 is an apocalyptic number.

138345520 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 138345520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (161741880).

138345520 is an abundant number, since it is smaller than the sum of its proper divisors (185138240).

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

138345520 is a wasteful number, since it uses less digits than its factorization.

138345520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9853 (or 9847 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 31.

The square root of 138345520 is about 11762.0372385059. The cubic root of 138345520 is about 517.1958523035.

The spelling of 138345520 in words is "one hundred thirty-eight million, three hundred forty-five thousand, five hundred twenty".