81758732 has 36 divisors (see below), whose sum is σ = 158128488. Its totient is φ = 36960000.

The previous prime is 81758731. The next prime is 81758741. The reversal of 81758732 is 23785718.

It is a self number, because there is not a number n which added to its sum of digits gives 81758732.

It is not an unprimeable number, because it can be changed into a prime (81758731) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 121148 + ... + 121820.

It is an arithmetic number, because the mean of its divisors is an integer number (4392458).

Almost surely, 2^81758732 is an apocalyptic number.

It is an amenable number.

81758732 is a deficient number, since it is larger than the sum of its proper divisors (76369756).

81758732 is a wasteful number, since it uses less digits than its factorization.

81758732 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 950 (or 937 counting only the distinct ones).

The product of its digits is 94080, while the sum is 41.

The square root of 81758732 is about 9042.0535278221. The cubic root of 81758732 is about 434.0216387945.

The spelling of 81758732 in words is "eighty-one million, seven hundred fifty-eight thousand, seven hundred thirty-two".