280972840 has 64 divisors (see below), whose sum is σ = 655464960. Its totient is φ = 108284160.

The previous prime is 280972831. The next prime is 280972843. The reversal of 280972840 is 48279082.

280972840 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 280972793 and 280972802.

It is not an unprimeable number, because it can be changed into a prime (280972843) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 429954 + ... + 430606.

It is an arithmetic number, because the mean of its divisors is an integer number (10241640).

Almost surely, 2^280972840 is an apocalyptic number.

280972840 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 280972840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (327732480).

280972840 is an abundant number, since it is smaller than the sum of its proper divisors (374492120).

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

280972840 is a wasteful number, since it uses less digits than its factorization.

280972840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1042 (or 1038 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 40.

The square root of 280972840 is about 16762.2444797825. The cubic root of 280972840 is about 654.9700586512.

The spelling of 280972840 in words is "two hundred eighty million, nine hundred seventy-two thousand, eight hundred forty".