81704064 has 96 divisors (see below), whose sum is σ = 235191600. Its totient is φ = 25119744.

The previous prime is 81704039. The next prime is 81704083. The reversal of 81704064 is 46040718.

It is a tau number, because it is divible by the number of its divisors (96).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 64267 + ... + 65525.

Almost surely, 2^81704064 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 81704064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117595800).

81704064 is an abundant number, since it is smaller than the sum of its proper divisors (153487536).

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

81704064 is a wasteful number, since it uses less digits than its factorization.

81704064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1302 (or 1277 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 30.

The square root of 81704064 is about 9039.0300364586. The cubic root of 81704064 is about 433.9248809938.

The spelling of 81704064 in words is "eighty-one million, seven hundred four thousand, sixty-four".