138281040 has 80 divisors (see below), whose sum is σ = 476308800. Its totient is φ = 36874368.

The previous prime is 138281023. The next prime is 138281041. The reversal of 138281040 is 40182831.

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

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 138280995 and 138281013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138281041) 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, 29850 + ... + 34169.

It is an arithmetic number, because the mean of its divisors is an integer number (5953860).

Almost surely, 2^138281040 is an apocalyptic number.

138281040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138281040 is an abundant number, since it is smaller than the sum of its proper divisors (338027760).

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

138281040 is a wasteful number, since it uses less digits than its factorization.

138281040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64041 (or 64029 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 138281040 is about 11759.2958972891. The cubic root of 138281040 is about 517.1154883689.

The spelling of 138281040 in words is "one hundred thirty-eight million, two hundred eighty-one thousand, forty".