81896064 has 64 divisors (see below), whose sum is σ = 218484000. Its totient is φ = 27180032.

The previous prime is 81896057. The next prime is 81896069. The reversal of 81896064 is 46069818.

It is a tau number, because it is divible by the number of its divisors (64).

It is not an unprimeable number, because it can be changed into a prime (81896069) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 160642 + ... + 161150.

Almost surely, 2^81896064 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 81896064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109242000).

81896064 is an abundant number, since it is smaller than the sum of its proper divisors (136587936).

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

81896064 is a wasteful number, since it uses less digits than its factorization.

81896064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 945 (or 933 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 42.

The square root of 81896064 is about 9049.6444129037. The cubic root of 81896064 is about 434.2645148602.

The spelling of 81896064 in words is "eighty-one million, eight hundred ninety-six thousand, sixty-four".