81688222824 has 32 divisors (see below), whose sum is σ = 219929831520. Its totient is φ = 25134837696.

The previous prime is 81688222813. The next prime is 81688222883. The reversal of 81688222824 is 42822288618.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

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, 130910302 + ... + 130910925.

It is an arithmetic number, because the mean of its divisors is an integer number (6872807235).

Almost surely, 2^81688222824 is an apocalyptic number.

It is an amenable number.

81688222824 is an abundant number, since it is smaller than the sum of its proper divisors (138241608696).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81688222824 is a wasteful number, since it uses less digits than its factorization.

81688222824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 261821249 (or 261821245 counting only the distinct ones).

The product of its digits is 1572864, while the sum is 51.

The spelling of 81688222824 in words is "eighty-one billion, six hundred eighty-eight million, two hundred twenty-two thousand, eight hundred twenty-four".