82005840 has 240 divisors, whose sum is σ = 321729408. Its totient is φ = 18330624.

The previous prime is 82005829. The next prime is 82005853. The reversal of 82005840 is 4850028.

82005840 is a `hidden beast` number, since 82 + 0 + 0 + 584 + 0 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 266967 + ... + 267273.

Almost surely, 2^82005840 is an apocalyptic number.

82005840 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 82005840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (160864704).

82005840 is an abundant number, since it is smaller than the sum of its proper divisors (239723568).

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

82005840 is a wasteful number, since it uses less digits than its factorization.

82005840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 386 (or 377 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 27.

The square root of 82005840 is about 9055.7075924524. The cubic root of 82005840 is about 434.4584620604.

Adding to 82005840 its reverse (4850028), we get a palindrome (86855868).

The spelling of 82005840 in words is "eighty-two million, five thousand, eight hundred forty".