280585505 has 4 divisors (see below), whose sum is σ = 336702612. Its totient is φ = 224468400.

The previous prime is 280585499. The next prime is 280585507. The reversal of 280585505 is 505585082.

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

It can be written as a sum of positive squares in 2 ways, for example, as 113891584 + 166693921 = 10672^2 + 12911^2 .

It is not a de Polignac number, because 280585505 - 2⁴ = 280585489 is a prime.

It is a super-2 number, since 2×280585505² = 157456451232210050, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (280585507) 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, 28058546 + ... + 28058555.

It is an arithmetic number, because the mean of its divisors is an integer number (84175653).

Almost surely, 2^280585505 is an apocalyptic number.

It is an amenable number.

280585505 is a deficient number, since it is larger than the sum of its proper divisors (56117107).

280585505 is an equidigital number, since it uses as much as digits as its factorization.

280585505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56117106.

The product of its (nonzero) digits is 80000, while the sum is 38.

The square root of 280585505 is about 16750.6867023415. The cubic root of 280585505 is about 654.6689506709.

The spelling of 280585505 in words is "two hundred eighty million, five hundred eighty-five thousand, five hundred five".