138447280 has 20 divisors (see below), whose sum is σ = 321890112. Its totient is φ = 55378880.

The previous prime is 138447251. The next prime is 138447293. The reversal of 138447280 is 82744831.

It is a tau number, because it is divible by the number of its divisors (20).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 865216 + ... + 865375.

Almost surely, 2^138447280 is an apocalyptic number.

138447280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138447280 is an abundant number, since it is smaller than the sum of its proper divisors (183442832).

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

138447280 is a wasteful number, since it uses less digits than its factorization.

138447280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1730604 (or 1730598 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 37.

The square root of 138447280 is about 11766.3622245790. The cubic root of 138447280 is about 517.3226289692.

The spelling of 138447280 in words is "one hundred thirty-eight million, four hundred forty-seven thousand, two hundred eighty".