281449520640 has 1120 divisors, whose sum is σ = 1082000747520. Its totient is φ = 70027296768.

The previous prime is 281449520633. The next prime is 281449520641. The reversal of 281449520640 is 46025944182.

It is a happy number.

281449520640 is a `hidden beast` number, since 2 + 81 + 4 + 4 + 9 + 520 + 6 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (281449520641) by changing a digit.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 3390958039 + ... + 3390958121.

It is an arithmetic number, because the mean of its divisors is an integer number (966072096).

Almost surely, 2^281449520640 is an apocalyptic number.

281449520640 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 281449520640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (541000373760).

281449520640 is an abundant number, since it is smaller than the sum of its proper divisors (800551226880).

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

281449520640 is an frugal number, since it uses more digits than its factorization.

281449520640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226 (or 195 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 45.

The spelling of 281449520640 in words is "two hundred eighty-one billion, four hundred forty-nine million, five hundred twenty thousand, six hundred forty".