280664 has 8 divisors (see below), whose sum is σ = 526260. Its totient is φ = 140328.

The previous prime is 280639. The next prime is 280673. The reversal of 280664 is 466082.

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

It is a plaindrome in base 9.

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 280664.

It is an unprimeable number.

280664 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 17534 + ... + 17549.

2²⁸⁰⁶⁶⁴ is an apocalyptic number.

It is an amenable number.

280664 is a deficient number, since it is larger than the sum of its proper divisors (245596).

280664 is a wasteful number, since it uses less digits than its factorization.

280664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35089 (or 35085 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 280664 is about 529.7773117075. Note that the first 3 decimals coincide. The cubic root of 280664 is about 65.4729993796.

The spelling of 280664 in words is "two hundred eighty thousand, six hundred sixty-four".