81172713 has 8 divisors (see below), whose sum is σ = 110533248. Its totient is φ = 52963664.

The previous prime is 81172699. The next prime is 81172753. The reversal of 81172713 is 31727118.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81172713 - 2⁶ = 81172649 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81172753) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 287706 + ... + 287987.

It is an arithmetic number, because the mean of its divisors is an integer number (13816656).

Almost surely, 2^81172713 is an apocalyptic number.

It is an amenable number.

81172713 is a deficient number, since it is larger than the sum of its proper divisors (29360535).

81172713 is a wasteful number, since it uses less digits than its factorization.

81172713 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 575743.

The product of its digits is 2352, while the sum is 30.

The square root of 81172713 is about 9009.5900572668. The cubic root of 81172713 is about 432.9821777765.

The spelling of 81172713 in words is "eighty-one million, one hundred seventy-two thousand, seven hundred thirteen".