84139 has 4 divisors (see below), whose sum is σ = 91800. Its totient is φ = 76480.

The previous prime is 84137. The next prime is 84143. The reversal of 84139 is 93148.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 84139 - 2¹ = 84137 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84131) 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, 3814 + ... + 3835.

It is an arithmetic number, because the mean of its divisors is an integer number (22950).

2⁸⁴¹³⁹ is an apocalyptic number.

84139 is a deficient number, since it is larger than the sum of its proper divisors (7661).

84139 is a wasteful number, since it uses less digits than its factorization.

84139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7660.

The product of its digits is 864, while the sum is 25.

The square root of 84139 is about 290.0672335856. The cubic root of 84139 is about 43.8193349579.

Subtracting 84139 from its reverse (93148), we obtain a palindrome (9009).

The spelling of 84139 in words is "eighty-four thousand, one hundred thirty-nine".