667845 has 40 divisors (see below), whose sum is σ = 1280664. Its totient is φ = 331776.

The previous prime is 667837. The next prime is 667859. The reversal of 667845 is 548766.

It is a happy number.

667845 is nontrivially palindromic in base 2.

It can be written as a sum of positive squares in 4 ways, for example, as 123201 + 544644 = 351^2 + 738^2 .

It is not a de Polignac number, because 667845 - 2³ = 667837 is a prime.

667845 is a lucky number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 6837 + ... + 6933.

2⁶⁶⁷⁸⁴⁵ is an apocalyptic number.

It is an amenable number.

667845 is a deficient number, since it is larger than the sum of its proper divisors (612819).

667845 is a wasteful number, since it uses less digits than its factorization.

667845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131 (or 122 counting only the distinct ones).

The product of its digits is 40320, while the sum is 36.

The square root of 667845 is about 817.2178412149. The cubic root of 667845 is about 87.4094846289.

The spelling of 667845 in words is "six hundred sixty-seven thousand, eight hundred forty-five".