81760218 has 8 divisors (see below), whose sum is σ = 163520448. Its totient is φ = 27253404.

The previous prime is 81760201. The next prime is 81760247. The reversal of 81760218 is 81206718.

It is a happy number.

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

81760218 is an admirable number.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

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, 6813346 + ... + 6813357.

It is an arithmetic number, because the mean of its divisors is an integer number (20440056).

Almost surely, 2^81760218 is an apocalyptic number.

81760218 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81760218 is a wasteful number, since it uses less digits than its factorization.

81760218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13626708.

The product of its (nonzero) digits is 5376, while the sum is 33.

The square root of 81760218 is about 9042.1356990481. The cubic root of 81760218 is about 434.0242682884.

The spelling of 81760218 in words is "eighty-one million, seven hundred sixty thousand, two hundred eighteen".