280981217940 has 96 divisors (see below), whose sum is σ = 801307145856. Its totient is φ = 73551421440.

The previous prime is 280981217911. The next prime is 280981217941. The reversal of 280981217940 is 49712189082.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (280981217941) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 772164 + ... + 1076196.

It is an arithmetic number, because the mean of its divisors is an integer number (8346949436).

Almost surely, 2^280981217940 is an apocalyptic number.

280981217940 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 280981217940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (400653572928).

280981217940 is an abundant number, since it is smaller than the sum of its proper divisors (520325927916).

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

280981217940 is a wasteful number, since it uses less digits than its factorization.

280981217940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 304329 (or 304327 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 51.

The spelling of 280981217940 in words is "two hundred eighty billion, nine hundred eighty-one million, two hundred seventeen thousand, nine hundred forty".