664187 has 8 divisors (see below), whose sum is σ = 706800. Its totient is φ = 622944.

The previous prime is 664177. The next prime is 664193. The reversal of 664187 is 781466.

664187 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 664187 - 2⁶ = 664123 is a prime.

It is a super-2 number, since 2×664187² = 882288741938, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664117) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 764 + ... + 1382.

It is an arithmetic number, because the mean of its divisors is an integer number (88350).

2⁶⁶⁴¹⁸⁷ is an apocalyptic number.

664187 is a deficient number, since it is larger than the sum of its proper divisors (42613).

664187 is a wasteful number, since it uses less digits than its factorization.

664187 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 685.

The product of its digits is 8064, while the sum is 32.

The square root of 664187 is about 814.9766867831. The cubic root of 664187 is about 87.2496024919.

The spelling of 664187 in words is "six hundred sixty-four thousand, one hundred eighty-seven".