664173 has 16 divisors (see below), whose sum is σ = 1042560. Its totient is φ = 416448.

The previous prime is 664151. The next prime is 664177. The reversal of 664173 is 371466.

It is not a de Polignac number, because 664173 - 2⁵ = 664141 is a prime.

It is a super-2 number, since 2×664173² = 882251547858, which contains 22 as substring.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 664173.

It is not an unprimeable number, because it can be changed into a prime (664177) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 265 + ... + 1182.

It is an arithmetic number, because the mean of its divisors is an integer number (65160).

2⁶⁶⁴¹⁷³ is an apocalyptic number.

It is an amenable number.

664173 is a deficient number, since it is larger than the sum of its proper divisors (378387).

664173 is a wasteful number, since it uses less digits than its factorization.

664173 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1473 (or 1467 counting only the distinct ones).

The product of its digits is 3024, while the sum is 27.

The square root of 664173 is about 814.9680975351. The cubic root of 664173 is about 87.2489894602.

The spelling of 664173 in words is "six hundred sixty-four thousand, one hundred seventy-three".