81988617222 has 24 divisors (see below), whose sum is σ = 177727367064. Its totient is φ = 27316406304.

The previous prime is 81988617169. The next prime is 81988617251. The reversal of 81988617222 is 22271688918.

81988617222 is a `hidden beast` number, since 8 + 19 + 8 + 8 + 617 + 2 + 2 + 2 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1055863 + ... + 1130850.

It is an arithmetic number, because the mean of its divisors is an integer number (7405306961).

Almost surely, 2^81988617222 is an apocalyptic number.

81988617222 is an abundant number, since it is smaller than the sum of its proper divisors (95738749842).

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

81988617222 is a wasteful number, since it uses less digits than its factorization.

81988617222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2188804 (or 2188801 counting only the distinct ones).

The product of its digits is 1548288, while the sum is 54.

The spelling of 81988617222 in words is "eighty-one billion, nine hundred eighty-eight million, six hundred seventeen thousand, two hundred twenty-two".