82081440 has 288 divisors, whose sum is σ = 339655680. Its totient is φ = 17620992.

The previous prime is 82081427. The next prime is 82081481. The reversal of 82081440 is 4418028.

It is a tau number, because it is divible by the number of its divisors (288).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 171121 + ... + 171599.

It is an arithmetic number, because the mean of its divisors is an integer number (1179360).

Almost surely, 2^82081440 is an apocalyptic number.

82081440 is a gapful number since it is divisible by the number (80) 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 82081440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (169827840).

82081440 is an abundant number, since it is smaller than the sum of its proper divisors (257574240).

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

82081440 is a wasteful number, since it uses less digits than its factorization.

82081440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 524 (or 513 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 27.

The square root of 82081440 is about 9059.8807939178. The cubic root of 82081440 is about 434.5919280500.

Adding to 82081440 its reverse (4418028), we get a palindrome (86499468).

The spelling of 82081440 in words is "eighty-two million, eighty-one thousand, four hundred forty".