138135240 has 256 divisors, whose sum is σ = 493516800. Its totient is φ = 34290432.

The previous prime is 138135223. The next prime is 138135241. The reversal of 138135240 is 42531831.

It is a happy number.

138135240 is a `hidden beast` number, since 138 + 1 + 3 + 524 + 0 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (138135241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1664239 + ... + 1664321.

It is an arithmetic number, because the mean of its divisors is an integer number (1927800).

Almost surely, 2^138135240 is an apocalyptic number.

138135240 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 138135240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (246758400).

138135240 is an abundant number, since it is smaller than the sum of its proper divisors (355381560).

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

138135240 is a wasteful number, since it uses less digits than its factorization.

138135240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 193 (or 183 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 138135240 is about 11753.0949115541. The cubic root of 138135240 is about 516.9336799974.

The spelling of 138135240 in words is "one hundred thirty-eight million, one hundred thirty-five thousand, two hundred forty".