138688550 has 192 divisors, whose sum is σ = 368976384. Its totient is φ = 37324800.

The previous prime is 138688519. The next prime is 138688553. The reversal of 138688550 is 55886831.

It is a super-2 number, since 2×138688550² = 38469027802205000, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138688553) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 850769 + ... + 850931.

It is an arithmetic number, because the mean of its divisors is an integer number (1921752).

Almost surely, 2^138688550 is an apocalyptic number.

138688550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

138688550 is an abundant number, since it is smaller than the sum of its proper divisors (230287834).

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

138688550 is a wasteful number, since it uses less digits than its factorization.

138688550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 223 (or 218 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 44.

The square root of 138688550 is about 11776.6102932890. The cubic root of 138688550 is about 517.6229647041.

The spelling of 138688550 in words is "one hundred thirty-eight million, six hundred eighty-eight thousand, five hundred fifty".