280881385 has 12 divisors (see below), whose sum is σ = 349086348. Its totient is φ = 216953408.

The previous prime is 280881383. The next prime is 280881413. The reversal of 280881385 is 583188082.

It can be written as a sum of positive squares in 6 ways, for example, as 10969344 + 269912041 = 3312^2 + 16429^2 .

It is not a de Polignac number, because 280881385 - 2¹ = 280881383 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (280881383) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 29194 + ... + 37603.

It is an arithmetic number, because the mean of its divisors is an integer number (29090529).

Almost surely, 2^280881385 is an apocalyptic number.

It is an amenable number.

280881385 is a deficient number, since it is larger than the sum of its proper divisors (68204963).

280881385 is an equidigital number, since it uses as much as digits as its factorization.

280881385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66860 (or 66831 counting only the distinct ones).

The product of its (nonzero) digits is 122880, while the sum is 43.

The square root of 280881385 is about 16759.5162519686. The cubic root of 280881385 is about 654.8989879776.

The spelling of 280881385 in words is "two hundred eighty million, eight hundred eighty-one thousand, three hundred eighty-five".