81367172 has 12 divisors (see below), whose sum is σ = 142961616. Its totient is φ = 40521000.

The previous prime is 81367163. The next prime is 81367211. The reversal of 81367172 is 27176318.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39518 + ... + 41525.

It is an arithmetic number, because the mean of its divisors is an integer number (11913468).

Almost surely, 2^81367172 is an apocalyptic number.

It is an amenable number.

81367172 is a deficient number, since it is larger than the sum of its proper divisors (61594444).

81367172 is a wasteful number, since it uses less digits than its factorization.

81367172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81298 (or 81296 counting only the distinct ones).

The product of its digits is 14112, while the sum is 35.

The square root of 81367172 is about 9020.3753802156. The cubic root of 81367172 is about 433.3276556784.

The spelling of 81367172 in words is "eighty-one million, three hundred sixty-seven thousand, one hundred seventy-two".