280138120 has 64 divisors (see below), whose sum is σ = 648426240. Its totient is φ = 108864000.

The previous prime is 280138099. The next prime is 280138139. The reversal of 280138120 is 21831082.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 465820 + ... + 466420.

It is an arithmetic number, because the mean of its divisors is an integer number (10131660).

Almost surely, 2^280138120 is an apocalyptic number.

280138120 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 280138120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (324213120).

280138120 is an abundant number, since it is smaller than the sum of its proper divisors (368288120).

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

280138120 is a wasteful number, since it uses less digits than its factorization.

280138120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 926 (or 922 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 280138120 is about 16737.3271462322. The cubic root of 280138120 is about 654.3208157068.

The spelling of 280138120 in words is "two hundred eighty million, one hundred thirty-eight thousand, one hundred twenty".