81338175 has 42 divisors (see below), whose sum is σ = 151253712. Its totient is φ = 43370640.

The previous prime is 81338171. The next prime is 81338207. The reversal of 81338175 is 57183318.

It is not a de Polignac number, because 81338175 - 2² = 81338171 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81338171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 41 ways as a sum of consecutive naturals, for example, 15994 + ... + 20456.

Almost surely, 2^81338175 is an apocalyptic number.

81338175 is a deficient number, since it is larger than the sum of its proper divisors (69915537).

81338175 is an equidigital number, since it uses as much as digits as its factorization.

81338175 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4491 (or 4471 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 81338175 is about 9018.7679313751. The cubic root of 81338175 is about 433.2761742490.

The spelling of 81338175 in words is "eighty-one million, three hundred thirty-eight thousand, one hundred seventy-five".