82111140 has 72 divisors (see below), whose sum is σ = 255822840. Its totient is φ = 21302784.

The previous prime is 82111109. The next prime is 82111147. The reversal of 82111140 is 4111128.

It can be written as a sum of positive squares in 4 ways, for example, as 2509056 + 79602084 = 1584^2 + 8922^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (82111147) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 496 + ... + 12824.

It is an arithmetic number, because the mean of its divisors is an integer number (3553095).

Almost surely, 2^82111140 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 82111140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (127911420).

82111140 is an abundant number, since it is smaller than the sum of its proper divisors (173711700).

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

82111140 is a wasteful number, since it uses less digits than its factorization.

82111140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12381 (or 12376 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

The square root of 82111140 is about 9061.5197400878. The cubic root of 82111140 is about 434.6443386957.

Adding to 82111140 its reverse (4111128), we get a palindrome (86222268).

The spelling of 82111140 in words is "eighty-two million, one hundred eleven thousand, one hundred forty".