81625175 has 6 divisors (see below), whose sum is σ = 101215248. Its totient is φ = 65300120.

The previous prime is 81625171. The next prime is 81625189. The reversal of 81625175 is 57152618.

It is not a de Polignac number, because 81625175 - 2² = 81625171 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81625171) 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 5 ways as a sum of consecutive naturals, for example, 1632479 + ... + 1632528.

It is an arithmetic number, because the mean of its divisors is an integer number (16869208).

Almost surely, 2^81625175 is an apocalyptic number.

81625175 is a deficient number, since it is larger than the sum of its proper divisors (19590073).

81625175 is a wasteful number, since it uses less digits than its factorization.

81625175 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3265017 (or 3265012 counting only the distinct ones).

The product of its digits is 16800, while the sum is 35.

The square root of 81625175 is about 9034.6651847205. The cubic root of 81625175 is about 433.7851779335.

The spelling of 81625175 in words is "eighty-one million, six hundred twenty-five thousand, one hundred seventy-five".