280447920 has 200 divisors, whose sum is σ = 985222656. Its totient is φ = 73930752.

The previous prime is 280447903. The next prime is 280447931. The reversal of 280447920 is 29744082.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 732049 + ... + 732431.

Almost surely, 2^280447920 is an apocalyptic number.

280447920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 280447920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (492611328).

280447920 is an abundant number, since it is smaller than the sum of its proper divisors (704774736).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

280447920 is a wasteful number, since it uses less digits than its factorization.

280447920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 521 (or 506 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 280447920 is about 16746.5793522140. The cubic root of 280447920 is about 654.5619276157.

The spelling of 280447920 in words is "two hundred eighty million, four hundred forty-seven thousand, nine hundred twenty".