81976736 has 24 divisors (see below), whose sum is σ = 166958820. Its totient is φ = 39574528.

The previous prime is 81976721. The next prime is 81976747. The reversal of 81976736 is 63767918.

It can be written as a sum of positive squares in 2 ways, for example, as 80640400 + 1336336 = 8980^2 + 1156^2 .

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, 43241 + ... + 45096.

Almost surely, 2^81976736 is an apocalyptic number.

It is an amenable number.

81976736 is an abundant number, since it is smaller than the sum of its proper divisors (84982084).

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

81976736 is a wasteful number, since it uses less digits than its factorization.

81976736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88376 (or 88368 counting only the distinct ones).

The product of its digits is 381024, while the sum is 47.

The square root of 81976736 is about 9054.1005075049. The cubic root of 81976736 is about 434.4070593180.

The spelling of 81976736 in words is "eighty-one million, nine hundred seventy-six thousand, seven hundred thirty-six".