81683111 has 8 divisors (see below), whose sum is σ = 86562000. Its totient is φ = 76941760.

The previous prime is 81683089. The next prime is 81683153. The reversal of 81683111 is 11138618.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81683111 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81683311) 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, 33161 + ... + 35538.

It is an arithmetic number, because the mean of its divisors is an integer number (10820250).

Almost surely, 2^81683111 is an apocalyptic number.

81683111 is a deficient number, since it is larger than the sum of its proper divisors (4878889).

81683111 is a wasteful number, since it uses less digits than its factorization.

81683111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68769.

The product of its digits is 1152, while the sum is 29.

The square root of 81683111 is about 9037.8709329133. The cubic root of 81683111 is about 433.8877844900.

The spelling of 81683111 in words is "eighty-one million, six hundred eighty-three thousand, one hundred eleven".