280961 has 4 divisors (see below), whose sum is σ = 282624. Its totient is φ = 279300.

The previous prime is 280957. The next prime is 280963. The reversal of 280961 is 169082.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 280961 - 2² = 280957 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 280961.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 280961.

It is not an unprimeable number, because it can be changed into a prime (280963) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 545 + ... + 926.

It is an arithmetic number, because the mean of its divisors is an integer number (70656).

2²⁸⁰⁹⁶¹ is an apocalyptic number.

It is an amenable number.

280961 is a deficient number, since it is larger than the sum of its proper divisors (1663).

280961 is a wasteful number, since it uses less digits than its factorization.

280961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1662.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 280961 is about 530.0575440459. The cubic root of 280961 is about 65.4960858528.

The spelling of 280961 in words is "two hundred eighty thousand, nine hundred sixty-one".