138784 has 12 divisors (see below), whose sum is σ = 273294. Its totient is φ = 69376.

The previous prime is 138763. The next prime is 138793. The reversal of 138784 is 487831.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 138384 + 400 = 372^2 + 20^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2137 + ... + 2200.

138784 is a Friedman number, since it can be written as 17348*8, using all its digits and the basic arithmetic operations.

2¹³⁸⁷⁸⁴ is an apocalyptic number.

It is an amenable number.

138784 is a deficient number, since it is larger than the sum of its proper divisors (134510).

138784 is an equidigital number, since it uses as much as digits as its factorization.

138784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4347 (or 4339 counting only the distinct ones).

The product of its digits is 5376, while the sum is 31.

The square root of 138784 is about 372.5372464600. The cubic root of 138784 is about 51.7741685828.

The spelling of 138784 in words is "one hundred thirty-eight thousand, seven hundred eighty-four".