667001 has 4 divisors (see below), whose sum is σ = 676212. Its totient is φ = 657792.

The previous prime is 666989. The next prime is 667013. The reversal of 667001 is 100766.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 100766 = 2 ⋅50383.

It is an interprime number because it is at equal distance from previous prime (666989) and next prime (667013).

It can be written as a sum of positive squares in 2 ways, for example, as 141376 + 525625 = 376^2 + 725^2 .

It is a cyclic number.

It is not a de Polignac number, because 667001 - 2⁶ = 666937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (667021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4496 + ... + 4641.

It is an arithmetic number, because the mean of its divisors is an integer number (169053).

2⁶⁶⁷⁰⁰¹ is an apocalyptic number.

It is an amenable number.

667001 is a deficient number, since it is larger than the sum of its proper divisors (9211).

667001 is an equidigital number, since it uses as much as digits as its factorization.

667001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9210.

The product of its (nonzero) digits is 252, while the sum is 20.

The square root of 667001 is about 816.7012917830. The cubic root of 667001 is about 87.3726473866.

Adding to 667001 its reverse (100766), we get a palindrome (767767).

The spelling of 667001 in words is "six hundred sixty-seven thousand, one".