281987940 has 48 divisors (see below), whose sum is σ = 850304448. Its totient is φ = 69412224.

The previous prime is 281987929. The next prime is 281987947. The reversal of 281987940 is 49789182.

It is a self number, because there is not a number n which added to its sum of digits gives 281987940.

It is not an unprimeable number, because it can be changed into a prime (281987947) 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, 179982 + ... + 181541.

It is an arithmetic number, because the mean of its divisors is an integer number (17714676).

Almost surely, 2^281987940 is an apocalyptic number.

281987940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

281987940 is an abundant number, since it is smaller than the sum of its proper divisors (568316508).

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

281987940 is a wasteful number, since it uses less digits than its factorization.

281987940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 361548 (or 361546 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 48.

The square root of 281987940 is about 16792.4965386330. The cubic root of 281987940 is about 655.7578703127.

The spelling of 281987940 in words is "two hundred eighty-one million, nine hundred eighty-seven thousand, nine hundred forty".