664851 has 8 divisors (see below), whose sum is σ = 967104. Its totient is φ = 402920.

The previous prime is 664849. The next prime is 664879. The reversal of 664851 is 158466.

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 664851 - 2¹ = 664849 is a prime.

It is not an unprimeable number, because it can be changed into a prime (664891) 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, 10041 + ... + 10106.

It is an arithmetic number, because the mean of its divisors is an integer number (120888).

2⁶⁶⁴⁸⁵¹ is an apocalyptic number.

664851 is a deficient number, since it is larger than the sum of its proper divisors (302253).

664851 is a wasteful number, since it uses less digits than its factorization.

664851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20161.

The product of its digits is 5760, while the sum is 30.

The square root of 664851 is about 815.3839586354. The cubic root of 664851 is about 87.2786678208.

The spelling of 664851 in words is "six hundred sixty-four thousand, eight hundred fifty-one".