667517 has 4 divisors (see below), whose sum is σ = 685596. Its totient is φ = 649440.

The previous prime is 667507. The next prime is 667519. The reversal of 667517 is 715766.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 715766 = 2 ⋅357883.

It can be written as a sum of positive squares in 2 ways, for example, as 290521 + 376996 = 539^2 + 614^2 .

It is a cyclic number.

It is not a de Polignac number, because 667517 - 2⁴ = 667501 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667519) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8984 + ... + 9057.

It is an arithmetic number, because the mean of its divisors is an integer number (171399).

2⁶⁶⁷⁵¹⁷ is an apocalyptic number.

It is an amenable number.

667517 is a deficient number, since it is larger than the sum of its proper divisors (18079).

667517 is a wasteful number, since it uses less digits than its factorization.

667517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18078.

The product of its digits is 8820, while the sum is 32.

The square root of 667517 is about 817.0171356832. The cubic root of 667517 is about 87.3951724228.

The spelling of 667517 in words is "six hundred sixty-seven thousand, five hundred seventeen".