81760217 has 16 divisors (see below), whose sum is σ = 102681600. Its totient is φ = 63242640.

The previous prime is 81760201. The next prime is 81760247. The reversal of 81760217 is 71206718.

81760217 is nontrivially palindromic in base 2.

It is a cyclic number.

It is not a de Polignac number, because 81760217 - 2⁴ = 81760201 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81760247) 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, 6884 + ... + 14522.

It is an arithmetic number, because the mean of its divisors is an integer number (6417600).

Almost surely, 2^81760217 is an apocalyptic number.

It is an amenable number.

81760217 is a deficient number, since it is larger than the sum of its proper divisors (20921383).

81760217 is a wasteful number, since it uses less digits than its factorization.

81760217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7796.

The product of its (nonzero) digits is 4704, while the sum is 32.

The square root of 81760217 is about 9042.1356437514. The cubic root of 81760217 is about 434.0242665189.

The spelling of 81760217 in words is "eighty-one million, seven hundred sixty thousand, two hundred seventeen".