138028280 has 64 divisors (see below), whose sum is σ = 342286560. Its totient is φ = 49771008.

The previous prime is 138028273. The next prime is 138028283. The reversal of 138028280 is 82820831.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138028283) 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, 19274 + ... + 25446.

Almost surely, 2^138028280 is an apocalyptic number.

138028280 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 138028280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (171143280).

138028280 is an abundant number, since it is smaller than the sum of its proper divisors (204258280).

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

138028280 is a wasteful number, since it uses less digits than its factorization.

138028280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6240 (or 6236 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 32.

The square root of 138028280 is about 11748.5437395449. The cubic root of 138028280 is about 516.8002226130.

The spelling of 138028280 in words is "one hundred thirty-eight million, twenty-eight thousand, two hundred eighty".