81676859 has 4 divisors (see below), whose sum is σ = 89102040. Its totient is φ = 74251680.

The previous prime is 81676849. The next prime is 81676867. The reversal of 81676859 is 95867618.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81676859 - 2⁴ = 81676843 is a prime.

It is a super-3 number, since 3×81676859³ (a number of 25 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81676849) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3712574 + ... + 3712595.

It is an arithmetic number, because the mean of its divisors is an integer number (22275510).

Almost surely, 2^81676859 is an apocalyptic number.

81676859 is a deficient number, since it is larger than the sum of its proper divisors (7425181).

81676859 is a wasteful number, since it uses less digits than its factorization.

81676859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7425180.

The product of its digits is 725760, while the sum is 50.

The square root of 81676859 is about 9037.5250483747. The cubic root of 81676859 is about 433.8767143287.

The spelling of 81676859 in words is "eighty-one million, six hundred seventy-six thousand, eight hundred fifty-nine".