81322859 has 4 divisors (see below), whose sum is σ = 81868800. Its totient is φ = 80776920.

The previous prime is 81322853. The next prime is 81322861. The reversal of 81322859 is 95822318.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81322859 is a prime.

It is a super-2 number, since 2×81322859² = 13226814791867762, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81322853) 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, 272747 + ... + 273044.

It is an arithmetic number, because the mean of its divisors is an integer number (20467200).

Almost surely, 2^81322859 is an apocalyptic number.

81322859 is a deficient number, since it is larger than the sum of its proper divisors (545941).

81322859 is a wasteful number, since it uses less digits than its factorization.

81322859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 545940.

The product of its digits is 34560, while the sum is 38.

The square root of 81322859 is about 9017.9187731982. The cubic root of 81322859 is about 433.2489772022.

The spelling of 81322859 in words is "eighty-one million, three hundred twenty-two thousand, eight hundred fifty-nine".