81432875 has 16 divisors (see below), whose sum is σ = 102424608. Its totient is φ = 64636000.

The previous prime is 81432863. The next prime is 81432881. The reversal of 81432875 is 57823418.

It is not a de Polignac number, because 81432875 - 2⁸ = 81432619 is a prime.

It is a Duffinian 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 15 ways as a sum of consecutive naturals, for example, 13889 + ... + 18861.

It is an arithmetic number, because the mean of its divisors is an integer number (6401538).

Almost surely, 2^81432875 is an apocalyptic number.

81432875 is a deficient number, since it is larger than the sum of its proper divisors (20991733).

81432875 is a wasteful number, since it uses less digits than its factorization.

81432875 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5119 (or 5109 counting only the distinct ones).

The product of its digits is 53760, while the sum is 38.

The square root of 81432875 is about 9024.0165669174. The cubic root of 81432875 is about 433.4442598993. Note that the first 3 decimals are identical.

The spelling of 81432875 in words is "eighty-one million, four hundred thirty-two thousand, eight hundred seventy-five".