82128312128 has 56 divisors (see below), whose sum is σ = 173454575112. Its totient is φ = 38448267264.

The previous prime is 82128312109. The next prime is 82128312131. The reversal of 82128312128 is 82121382128.

It can be written as a sum of positive squares in 4 ways, for example, as 32402880064 + 49725432064 = 180008^2 + 222992^2 .

It is a junction number, because it is equal to n+sod(n) for n = 82128312091 and 82128312100.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14426 + ... + 405542.

It is an arithmetic number, because the mean of its divisors is an integer number (3097403127).

Almost surely, 2^82128312128 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 82128312128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86727287556).

82128312128 is an abundant number, since it is smaller than the sum of its proper divisors (91326262984).

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

82128312128 is a wasteful number, since it uses less digits than its factorization.

82128312128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 391339 (or 391329 counting only the distinct ones).

The product of its digits is 24576, while the sum is 38.

The spelling of 82128312128 in words is "eighty-two billion, one hundred twenty-eight million, three hundred twelve thousand, one hundred twenty-eight".