667139 has 4 divisors (see below), whose sum is σ = 727800. Its totient is φ = 606480.

The previous prime is 667129. The next prime is 667141. The reversal of 667139 is 931766.

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 667139 - 2⁴ = 667123 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (667129) 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, 30314 + ... + 30335.

It is an arithmetic number, because the mean of its divisors is an integer number (181950).

2⁶⁶⁷¹³⁹ is an apocalyptic number.

667139 is a deficient number, since it is larger than the sum of its proper divisors (60661).

667139 is a wasteful number, since it uses less digits than its factorization.

667139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60660.

The product of its digits is 6804, while the sum is 32.

The square root of 667139 is about 816.7857736273. The cubic root of 667139 is about 87.3786726618.

It can be divided in two parts, 66 and 7139, that multiplied together give a palindrome (471174).

The spelling of 667139 in words is "six hundred sixty-seven thousand, one hundred thirty-nine".