138623040 has 168 divisors, whose sum is σ = 481827840. Its totient is φ = 36578304.

The previous prime is 138623029. The next prime is 138623059. The reversal of 138623040 is 40326831.

It is a happy number.

138623040 is a `hidden beast` number, since 1 + 38 + 623 + 0 + 4 + 0 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 138622995 and 138623013.

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, 365571 + ... + 365949.

Almost surely, 2^138623040 is an apocalyptic number.

138623040 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 138623040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (240913920).

138623040 is an abundant number, since it is smaller than the sum of its proper divisors (343204800).

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

138623040 is a wasteful number, since it uses less digits than its factorization.

138623040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 529 (or 516 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 138623040 is about 11773.8286041542. The cubic root of 138623040 is about 517.5414515561.

Adding to 138623040 its reverse (40326831), we get a palindrome (178949871).

The spelling of 138623040 in words is "one hundred thirty-eight million, six hundred twenty-three thousand, forty".