81682704 has 60 divisors (see below), whose sum is σ = 230117836. Its totient is φ = 27046656.

The previous prime is 81682703. The next prime is 81682709. The reversal of 81682704 is 40728618.

It can be written as a sum of positive squares in 2 ways, for example, as 7033104 + 74649600 = 2652^2 + 8640^2 .

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 (81682703) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20802 + ... + 24414.

Almost surely, 2^81682704 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 81682704, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (115058918).

81682704 is an abundant number, since it is smaller than the sum of its proper divisors (148435132).

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

81682704 is a wasteful number, since it uses less digits than its factorization.

81682704 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3784 (or 3775 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 81682704 is about 9037.8484165204. The cubic root of 81682704 is about 433.8870638489.

The spelling of 81682704 in words is "eighty-one million, six hundred eighty-two thousand, seven hundred four".