81964896 has 48 divisors (see below), whose sum is σ = 231711984. Its totient is φ = 25219584.

The previous prime is 81964877. The next prime is 81964901. The reversal of 81964896 is 69846918.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (48).

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 31591 + ... + 34086.

It is an arithmetic number, because the mean of its divisors is an integer number (4827333).

Almost surely, 2^81964896 is an apocalyptic number.

It is an amenable number.

81964896 is an abundant number, since it is smaller than the sum of its proper divisors (149747088).

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

81964896 is a wasteful number, since it uses less digits than its factorization.

81964896 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65703 (or 65695 counting only the distinct ones).

The product of its digits is 746496, while the sum is 51.

The square root of 81964896 is about 9053.4466365026. The cubic root of 81964896 is about 434.3861443305.

The spelling of 81964896 in words is "eighty-one million, nine hundred sixty-four thousand, eight hundred ninety-six".