138868544 has 14 divisors (see below), whose sum is σ = 275567394. Its totient is φ = 69434240.

The previous prime is 138868487. The next prime is 138868547. The reversal of 138868544 is 445868831.

It can be written as a sum of positive squares in only one way, i.e., 133633600 + 5234944 = 11560^2 + 2288^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138868547) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1084847 + ... + 1084974.

Almost surely, 2^138868544 is an apocalyptic number.

It is an amenable number.

138868544 is a deficient number, since it is larger than the sum of its proper divisors (136698850).

138868544 is an equidigital number, since it uses as much as digits as its factorization.

138868544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2169833 (or 2169823 counting only the distinct ones).

The product of its digits is 737280, while the sum is 47.

The square root of 138868544 is about 11784.2498276301. The cubic root of 138868544 is about 517.8467965708.

The spelling of 138868544 in words is "one hundred thirty-eight million, eight hundred sixty-eight thousand, five hundred forty-four".