138006540 has 108 divisors (see below), whose sum is σ = 486997056. Its totient is φ = 31542336.

The previous prime is 138006521. The next prime is 138006551. The reversal of 138006540 is 45600831.

138006540 is a `hidden beast` number, since 1 + 3 + 8 + 0 + 0 + 654 + 0 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 997 + ... + 16643.

It is an arithmetic number, because the mean of its divisors is an integer number (4509232).

Almost surely, 2^138006540 is an apocalyptic number.

138006540 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 138006540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (243498528).

138006540 is an abundant number, since it is smaller than the sum of its proper divisors (348990516).

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

138006540 is a wasteful number, since it uses less digits than its factorization.

138006540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15676 (or 15664 counting only the distinct ones).

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

The square root of 138006540 is about 11747.6184820584. The cubic root of 138006540 is about 516.7730884954.

The spelling of 138006540 in words is "one hundred thirty-eight million, six thousand, five hundred forty".