81825370284 has 288 divisors, whose sum is σ = 242694144000. Its totient is φ = 21319562880.

The previous prime is 81825370279. The next prime is 81825370307. The reversal of 81825370284 is 48207352818.

It is a super-2 number, since 2×81825370284² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 34106917 + ... + 34109315.

It is an arithmetic number, because the mean of its divisors is an integer number (842688000).

Almost surely, 2^81825370284 is an apocalyptic number.

81825370284 is a gapful number since it is divisible by the number (84) 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 81825370284, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (121347072000).

81825370284 is an abundant number, since it is smaller than the sum of its proper divisors (160868773716).

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

81825370284 is a wasteful number, since it uses less digits than its factorization.

81825370284 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2553 (or 2544 counting only the distinct ones).

The product of its (nonzero) digits is 860160, while the sum is 48.

The spelling of 81825370284 in words is "eighty-one billion, eight hundred twenty-five million, three hundred seventy thousand, two hundred eighty-four".