664611 has 4 divisors (see below), whose sum is σ = 886152. Its totient is φ = 443072.

The previous prime is 664603. The next prime is 664613. The reversal of 664611 is 116466.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 664611 - 2³ = 664603 is a prime.

It is a D-number.

It is not an unprimeable number, because it can be changed into a prime (664613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 110766 + ... + 110771.

It is an arithmetic number, because the mean of its divisors is an integer number (221538).

2⁶⁶⁴⁶¹¹ is an apocalyptic number.

664611 is a deficient number, since it is larger than the sum of its proper divisors (221541).

664611 is a wasteful number, since it uses less digits than its factorization.

664611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221540.

The product of its digits is 864, while the sum is 24.

The square root of 664611 is about 815.2367754217. The cubic root of 664611 is about 87.2681645145.

It can be divided in two parts, 664 and 611, that added together give a triangular number (1275 = T₅₀).

The spelling of 664611 in words is "six hundred sixty-four thousand, six hundred eleven".