81829440000 has 2000 divisors, whose sum is σ = 389791676736. Its totient is φ = 16588800000.

The previous prime is 81829439981. The next prime is 81829440001. The reversal of 81829440000 is 4492818.

It is a tau number, because it is divible by the number of its divisors (2000).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (81829440001) 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 199 ways as a sum of consecutive naturals, for example, 1995839980 + ... + 1995840020.

Almost surely, 2^81829440000 is an apocalyptic number.

81829440000 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 81829440000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (194895838368).

81829440000 is an abundant number, since it is smaller than the sum of its proper divisors (307962236736).

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

81829440000 is an equidigital number, since it uses as much as digits as its factorization.

81829440000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109 (or 69 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

It can be divided in two parts, 81 and 829440000, that multiplied together give a square (67184640000 = 259200²).

The spelling of 81829440000 in words is "eighty-one billion, eight hundred twenty-nine million, four hundred forty thousand".