281399040 has 216 divisors, whose sum is σ = 1049062560. Its totient is φ = 69230592.

The previous prime is 281399021. The next prime is 281399051. The reversal of 281399040 is 40993182.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 281398986 and 281399004.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 148821 + ... + 150699.

Almost surely, 2^281399040 is an apocalyptic number.

281399040 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 281399040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (524531280).

281399040 is an abundant number, since it is smaller than the sum of its proper divisors (767663520).

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

281399040 is a wasteful number, since it uses less digits than its factorization.

281399040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1919 (or 1902 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 281399040 is about 16774.9527570125. The cubic root of 281399040 is about 655.3010600553.

The spelling of 281399040 in words is "two hundred eighty-one million, three hundred ninety-nine thousand, forty".