81756704 has 12 divisors (see below), whose sum is σ = 160958574. Its totient is φ = 40878336.

The previous prime is 81756679. The next prime is 81756721. The reversal of 81756704 is 40765718.

It can be written as a sum of positive squares in only one way, i.e., 80066704 + 1690000 = 8948^2 + 1300^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1277417 + ... + 1277480.

Almost surely, 2^81756704 is an apocalyptic number.

It is an amenable number.

81756704 is a deficient number, since it is larger than the sum of its proper divisors (79201870).

81756704 is a wasteful number, since it uses less digits than its factorization.

81756704 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2554907 (or 2554899 counting only the distinct ones).

The product of its (nonzero) digits is 47040, while the sum is 38.

The square root of 81756704 is about 9041.9413844594. The cubic root of 81756704 is about 434.0180501741.

The spelling of 81756704 in words is "eighty-one million, seven hundred fifty-six thousand, seven hundred four".