81888866669 has 8 divisors (see below), whose sum is σ = 91269325440. Its totient is φ = 73015459776.

The previous prime is 81888866663. The next prime is 81888866693. The reversal of 81888866669 is 96666888818.

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 81888866669 - 2²⁰ = 81887818093 is a prime.

It is a super-2 number, since 2×81888866669² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81888866596 and 81888866605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81888866663) 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 7 ways as a sum of consecutive naturals, for example, 126762629 + ... + 126763274.

It is an arithmetic number, because the mean of its divisors is an integer number (11408665680).

Almost surely, 2^81888866669 is an apocalyptic number.

It is an amenable number.

81888866669 is a deficient number, since it is larger than the sum of its proper divisors (9380458771).

81888866669 is a wasteful number, since it uses less digits than its factorization.

81888866669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 253525939.

The product of its digits is 382205952, while the sum is 74.

The spelling of 81888866669 in words is "eighty-one billion, eight hundred eighty-eight million, eight hundred sixty-six thousand, six hundred sixty-nine".