81672625 has 16 divisors (see below), whose sum is σ = 102345984. Its totient is φ = 65070000.

The previous prime is 81672623. The next prime is 81672667. The reversal of 81672625 is 52627618.

It is a happy number.

It is not a de Polignac number, because 81672625 - 2¹ = 81672623 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81672623) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32670 + ... + 35080.

It is an arithmetic number, because the mean of its divisors is an integer number (6396624).

Almost surely, 2^81672625 is an apocalyptic number.

It is an amenable number.

81672625 is a deficient number, since it is larger than the sum of its proper divisors (20673359).

81672625 is a wasteful number, since it uses less digits than its factorization.

81672625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2697 (or 2687 counting only the distinct ones).

The product of its digits is 40320, while the sum is 37.

The square root of 81672625 is about 9037.2907997917. The cubic root of 81672625 is about 433.8692170369.

It can be divided in two parts, 816 and 72625, that added together give a square (73441 = 271²).

The spelling of 81672625 in words is "eighty-one million, six hundred seventy-two thousand, six hundred twenty-five".