667831 has 4 divisors (see below), whose sum is σ = 703000. Its totient is φ = 632664.

The previous prime is 667829. The next prime is 667837. The reversal of 667831 is 138766.

667831 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 138766 = 2 ⋅69383.

It is a cyclic number.

It is not a de Polignac number, because 667831 - 2¹ = 667829 is a prime.

It is a super-2 number, since 2×667831² = 891996489122, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 667793 and 667802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667837) 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, 17556 + ... + 17593.

It is an arithmetic number, because the mean of its divisors is an integer number (175750).

2⁶⁶⁷⁸³¹ is an apocalyptic number.

667831 is a deficient number, since it is larger than the sum of its proper divisors (35169).

667831 is a wasteful number, since it uses less digits than its factorization.

667831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35168.

The product of its digits is 6048, while the sum is 31.

The square root of 667831 is about 817.2092755225. The cubic root of 667831 is about 87.4088738378.

The spelling of 667831 in words is "six hundred sixty-seven thousand, eight hundred thirty-one".