281323920 has 80 divisors (see below), whose sum is σ = 878068800. Its totient is φ = 74506752.

The previous prime is 281323909. The next prime is 281323921. The reversal of 281323920 is 29323182.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (281323921) 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, 31827 + ... + 39693.

It is an arithmetic number, because the mean of its divisors is an integer number (10975860).

Almost surely, 2^281323920 is an apocalyptic number.

281323920 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 281323920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (439034400).

281323920 is an abundant number, since it is smaller than the sum of its proper divisors (596744880).

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

281323920 is a wasteful number, since it uses less digits than its factorization.

281323920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8032 (or 8026 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 281323920 is about 16772.7135550572. The cubic root of 281323920 is about 655.2427435846.

The spelling of 281323920 in words is "two hundred eighty-one million, three hundred twenty-three thousand, nine hundred twenty".