280509987 has 16 divisors (see below), whose sum is σ = 393496992. Its totient is φ = 177511680.

The previous prime is 280509967. The next prime is 280510003. The reversal of 280509987 is 789905082.

It is a happy number.

It is not a de Polignac number, because 280509987 - 2²⁰ = 279461411 is a prime.

It is not an unprimeable number, because it can be changed into a prime (280509937) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26268 + ... + 35369.

It is an arithmetic number, because the mean of its divisors is an integer number (24593562).

Almost surely, 2^280509987 is an apocalyptic number.

280509987 is a deficient number, since it is larger than the sum of its proper divisors (112987005).

280509987 is a wasteful number, since it uses less digits than its factorization.

280509987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61718.

The product of its (nonzero) digits is 362880, while the sum is 48.

The square root of 280509987 is about 16748.4323744045. The cubic root of 280509987 is about 654.6102119204.

The spelling of 280509987 in words is "two hundred eighty million, five hundred nine thousand, nine hundred eighty-seven".