81717844467 has 16 divisors (see below), whose sum is σ = 127887901952. Its totient is φ = 45433859040.

The previous prime is 81717844463. The next prime is 81717844501. The reversal of 81717844467 is 76444871718.

It is not a de Polignac number, because 81717844467 - 2² = 81717844463 is a prime.

It is a super-2 number, since 2×81717844467² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81717844463) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 52584709 + ... + 52586262.

It is an arithmetic number, because the mean of its divisors is an integer number (7992993872).

Almost surely, 2^81717844467 is an apocalyptic number.

81717844467 is a deficient number, since it is larger than the sum of its proper divisors (46170057485).

81717844467 is a wasteful number, since it uses less digits than its factorization.

81717844467 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105171018.

The product of its digits is 8429568, while the sum is 57.

The spelling of 81717844467 in words is "eighty-one billion, seven hundred seventeen million, eight hundred forty-four thousand, four hundred sixty-seven".