138881944 has 32 divisors (see below), whose sum is σ = 275328000. Its totient is φ = 65493792.

The previous prime is 138881927. The next prime is 138881987. The reversal of 138881944 is 449188831.

It is a Smith number, since the sum of its digits (46) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 138881894 and 138881903.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34417 + ... + 38239.

It is an arithmetic number, because the mean of its divisors is an integer number (8604000).

Almost surely, 2^138881944 is an apocalyptic number.

It is an amenable number.

138881944 is a deficient number, since it is larger than the sum of its proper divisors (136446056).

138881944 is a wasteful number, since it uses less digits than its factorization.

138881944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4087 (or 4083 counting only the distinct ones).

The product of its digits is 221184, while the sum is 46.

The square root of 138881944 is about 11784.8183694107. The cubic root of 138881944 is about 517.8634524280.

The spelling of 138881944 in words is "one hundred thirty-eight million, eight hundred eighty-one thousand, nine hundred forty-four".