280020 has 48 divisors (see below), whose sum is σ = 846720. Its totient is φ = 68736.

The previous prime is 280013. The next prime is 280031. The reversal of 280020 is 20082.

It is a super-2 number, since 2×280020² = 156822400800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 279978 and 280005.

It is a congruent number.

It is an unprimeable number.

280020 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 601 + ... + 959.

It is an arithmetic number, because the mean of its divisors is an integer number (17640).

2²⁸⁰⁰²⁰ is an apocalyptic number.

280020 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 280020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (423360).

280020 is an abundant number, since it is smaller than the sum of its proper divisors (566700).

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

280020 is a wasteful number, since it uses less digits than its factorization.

280020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 384 (or 382 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 280020 is about 529.1691600991. The cubic root of 280020 is about 65.4228838173.

The spelling of 280020 in words is "two hundred eighty thousand, twenty".