81296736 has 24 divisors (see below), whose sum is σ = 213404184. Its totient is φ = 27098880.

The previous prime is 81296711. The next prime is 81296741. The reversal of 81296736 is 63769218.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (24).

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 3 ways as a sum of consecutive naturals, for example, 423325 + ... + 423516.

It is an arithmetic number, because the mean of its divisors is an integer number (8891841).

Almost surely, 2^81296736 is an apocalyptic number.

It is an amenable number.

81296736 is an abundant number, since it is smaller than the sum of its proper divisors (132107448).

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

81296736 is a wasteful number, since it uses less digits than its factorization.

81296736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 846854 (or 846846 counting only the distinct ones).

The product of its digits is 108864, while the sum is 42.

The square root of 81296736 is about 9016.4702628024. The cubic root of 81296736 is about 433.2025819851.

The spelling of 81296736 in words is "eighty-one million, two hundred ninety-six thousand, seven hundred thirty-six".