438139 has 4 divisors (see below), whose sum is σ = 471856. Its totient is φ = 404424.

The previous prime is 438133. The next prime is 438143. The reversal of 438139 is 931834.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 931834 = 2 ⋅465917.

It is a cyclic number.

It is not a de Polignac number, because 438139 - 2³ = 438131 is a prime.

It is a Duffinian number.

438139 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (438131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16839 + ... + 16864.

It is an arithmetic number, because the mean of its divisors is an integer number (117964).

2⁴³⁸¹³⁹ is an apocalyptic number.

438139 is a deficient number, since it is larger than the sum of its proper divisors (33717).

438139 is a wasteful number, since it uses less digits than its factorization.

438139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33716.

The product of its digits is 2592, while the sum is 28.

The square root of 438139 is about 661.9206901132. The cubic root of 438139 is about 75.9516659432.

The spelling of 438139 in words is "four hundred thirty-eight thousand, one hundred thirty-nine".