281220000 has 240 divisors, whose sum is σ = 952570080. Its totient is φ = 72576000.

The previous prime is 281219963. The next prime is 281220029. The reversal of 281220000 is 22182.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 2579946 + ... + 2580054.

It is an arithmetic number, because the mean of its divisors is an integer number (3969042).

Almost surely, 2^281220000 is an apocalyptic number.

281220000 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 281220000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (476285040).

281220000 is an abundant number, since it is smaller than the sum of its proper divisors (671350080).

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

281220000 is a wasteful number, since it uses less digits than its factorization.

281220000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185 (or 162 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 281220000 is about 16769.6153802048. The cubic root of 281220000 is about 655.1620522448.

Adding to 281220000 its reverse (22182), we get a palindrome (281242182).

The spelling of 281220000 in words is "two hundred eighty-one million, two hundred twenty thousand".