81608000 has 84 divisors (see below), whose sum is σ = 204123036. Its totient is φ = 32320000.

The previous prime is 81607993. The next prime is 81608003. The reversal of 81608000 is 80618.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 6 ways, for example, as 30976 + 81577024 = 176^2 + 9032^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81608003) 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 11 ways as a sum of consecutive naturals, for example, 807950 + ... + 808050.

Almost surely, 2^81608000 is an apocalyptic number.

81608000 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 81608000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (102061518).

81608000 is an abundant number, since it is smaller than the sum of its proper divisors (122515036).

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

81608000 is an equidigital number, since it uses as much as digits as its factorization.

81608000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229 (or 108 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 23.

The square root of 81608000 is about 9033.7146290992. The cubic root of 81608000 is about 433.7547511155.

Adding to 81608000 its reverse (80618), we get a palindrome (81688618).

The spelling of 81608000 in words is "eighty-one million, six hundred eight thousand".