139873 has 4 divisors (see below), whose sum is σ = 142228. Its totient is φ = 137520.

The previous prime is 139871. The next prime is 139883. The reversal of 139873 is 378931.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 378931 = 7 ⋅54133.

It can be written as a sum of positive squares in 2 ways, for example, as 18769 + 121104 = 137^2 + 348^2 .

It is a cyclic number.

It is not a de Polignac number, because 139873 - 2¹ = 139871 is a prime.

It is a super-2 number, since 2×139873² = 39128912258, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139871) 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, 1086 + ... + 1207.

It is an arithmetic number, because the mean of its divisors is an integer number (35557).

2¹³⁹⁸⁷³ is an apocalyptic number.

It is an amenable number.

139873 is a deficient number, since it is larger than the sum of its proper divisors (2355).

139873 is an equidigital number, since it uses as much as digits as its factorization.

139873 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2354.

The product of its digits is 4536, while the sum is 31.

The square root of 139873 is about 373.9959892833. The cubic root of 139873 is about 51.9092351553.

The spelling of 139873 in words is "one hundred thirty-nine thousand, eight hundred seventy-three".