138856840 has 16 divisors (see below), whose sum is σ = 312427980. Its totient is φ = 55542720.

The previous prime is 138856811. The next prime is 138856853. The reversal of 138856840 is 48658831.

It can be written as a sum of positive squares in 2 ways, for example, as 128731716 + 10125124 = 11346^2 + 3182^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1735671 + ... + 1735750.

Almost surely, 2^138856840 is an apocalyptic number.

138856840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138856840 is an abundant number, since it is smaller than the sum of its proper divisors (173571140).

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

138856840 is a wasteful number, since it uses less digits than its factorization.

138856840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3471432 (or 3471428 counting only the distinct ones).

The product of its (nonzero) digits is 184320, while the sum is 43.

The square root of 138856840 is about 11783.7532221275. The cubic root of 138856840 is about 517.8322479216.

The spelling of 138856840 in words is "one hundred thirty-eight million, eight hundred fifty-six thousand, eight hundred forty".