81710081 has 8 divisors (see below), whose sum is σ = 84654720. Its totient is φ = 78773968.

The previous prime is 81710039. The next prime is 81710093. The reversal of 81710081 is 18001718.

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 81710081 - 2¹⁴ = 81693697 is a prime.

It is a super-2 number, since 2×81710081² = 13353074674053122, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 81710081.

It is not an unprimeable number, because it can be changed into a prime (81718081) 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, 22280 + ... + 25686.

It is an arithmetic number, because the mean of its divisors is an integer number (10581840).

Almost surely, 2^81710081 is an apocalyptic number.

It is an amenable number.

81710081 is a deficient number, since it is larger than the sum of its proper divisors (2944639).

81710081 is a wasteful number, since it uses less digits than its factorization.

81710081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4263.

The product of its (nonzero) digits is 448, while the sum is 26.

The square root of 81710081 is about 9039.3628647156. The cubic root of 81710081 is about 433.9355326954.

Adding to 81710081 its reverse (18001718), we get a palindrome (99711799).

The spelling of 81710081 in words is "eighty-one million, seven hundred ten thousand, eighty-one".