81535736 has 16 divisors (see below), whose sum is σ = 159526800. Its totient is φ = 38995264.

The previous prime is 81535693. The next prime is 81535763. The reversal of 81535736 is 63753518.

It is a self number, because there is not a number n which added to its sum of digits gives 81535736.

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, 221381 + ... + 221748.

It is an arithmetic number, because the mean of its divisors is an integer number (9970425).

Almost surely, 2^81535736 is an apocalyptic number.

It is an amenable number.

81535736 is a deficient number, since it is larger than the sum of its proper divisors (77991064).

81535736 is a wasteful number, since it uses less digits than its factorization.

81535736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 443158 (or 443154 counting only the distinct ones).

The product of its digits is 75600, while the sum is 38.

The square root of 81535736 is about 9029.7140597031. The cubic root of 81535736 is about 433.6266831571.

The spelling of 81535736 in words is "eighty-one million, five hundred thirty-five thousand, seven hundred thirty-six".