81706773 has 8 divisors (see below), whose sum is σ = 109077408. Its totient is φ = 54403664.

The previous prime is 81706763. The next prime is 81706831. The reversal of 81706773 is 37760718.

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 81706773 - 2²⁰ = 80658197 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81706753) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13986 + ... + 18947.

It is an arithmetic number, because the mean of its divisors is an integer number (13634676).

Almost surely, 2^81706773 is an apocalyptic number.

It is an amenable number.

81706773 is a deficient number, since it is larger than the sum of its proper divisors (27370635).

81706773 is a wasteful number, since it uses less digits than its factorization.

81706773 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33763.

The product of its (nonzero) digits is 49392, while the sum is 39.

The square root of 81706773 is about 9039.1798853657. The cubic root of 81706773 is about 433.9296767141.

The spelling of 81706773 in words is "eighty-one million, seven hundred six thousand, seven hundred seventy-three".