138055280 has 80 divisors (see below), whose sum is σ = 356227200. Its totient is φ = 49332480.

The previous prime is 138055279. The next prime is 138055289. The reversal of 138055280 is 82550831.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138055289) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50591 + ... + 53249.

It is an arithmetic number, because the mean of its divisors is an integer number (4452840).

Almost surely, 2^138055280 is an apocalyptic number.

138055280 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 138055280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (178113600).

138055280 is an abundant number, since it is smaller than the sum of its proper divisors (218171920).

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

138055280 is a wasteful number, since it uses less digits than its factorization.

138055280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2742 (or 2736 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 32.

The square root of 138055280 is about 11749.6927619406. The cubic root of 138055280 is about 516.8339178728.

The spelling of 138055280 in words is "one hundred thirty-eight million, fifty-five thousand, two hundred eighty".