810664 has 8 divisors (see below), whose sum is σ = 1520010. Its totient is φ = 405328.

The previous prime is 810659. The next prime is 810671. The reversal of 810664 is 466018.

810664 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 550564 + 260100 = 742^2 + 510^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×810664² = 1314352241792, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50659 + ... + 50674.

2⁸¹⁰⁶⁶⁴ is an apocalyptic number.

It is an amenable number.

810664 is a deficient number, since it is larger than the sum of its proper divisors (709346).

810664 is a wasteful number, since it uses less digits than its factorization.

810664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101339 (or 101335 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 810664 is about 900.3688133204. The cubic root of 810664 is about 93.2424398560.

The spelling of 810664 in words is "eight hundred ten thousand, six hundred sixty-four".