138587040 has 144 divisors (see below), whose sum is σ = 476716968. Its totient is φ = 36661248.

The previous prime is 138587039. The next prime is 138587087. The reversal of 138587040 is 40785831.

138587040 is a `hidden beast` number, since 1 + 38 + 587 + 0 + 40 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 48944016 + 89643024 = 6996^2 + 9468^2 .

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 138586986 and 138587004.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 225774 + ... + 226386.

Almost surely, 2^138587040 is an apocalyptic number.

138587040 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 138587040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (238358484).

138587040 is an abundant number, since it is smaller than the sum of its proper divisors (338129928).

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

138587040 is a wasteful number, since it uses less digits than its factorization.

138587040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 791 (or 780 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

The square root of 138587040 is about 11772.2996903749. The cubic root of 138587040 is about 517.4966463411.

The spelling of 138587040 in words is "one hundred thirty-eight million, five hundred eighty-seven thousand, forty".