138855040 has 96 divisors (see below), whose sum is σ = 350923860. Its totient is φ = 52531200.

The previous prime is 138855029. The next prime is 138855047. The reversal of 138855040 is 40558831.

It can be written as a sum of positive squares in 2 ways, for example, as 136983616 + 1871424 = 11704^2 + 1368^2 .

It is a junction number, because it is equal to n+sod(n) for n = 138854987 and 138855005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138855047) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 230740 + ... + 231340.

Almost surely, 2^138855040 is an apocalyptic number.

138855040 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 138855040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (175461930).

138855040 is an abundant number, since it is smaller than the sum of its proper divisors (212068820).

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

138855040 is an equidigital number, since it uses as much as digits as its factorization.

138855040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 658 (or 627 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 34.

The square root of 138855040 is about 11783.6768455351. The cubic root of 138855040 is about 517.8300103603.

The spelling of 138855040 in words is "one hundred thirty-eight million, eight hundred fifty-five thousand, forty".