81123551170 has 16 divisors (see below), whose sum is σ = 149968943928. Its totient is φ = 31572408960.

The previous prime is 81123551161. The next prime is 81123551221. The reversal of 81123551170 is 7115532118.

It can be written as a sum of positive squares in 4 ways, for example, as 75214708009 + 5908843161 = 274253^2 + 76869^2 .

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, 109626051 + ... + 109626790.

Almost surely, 2^81123551170 is an apocalyptic number.

81123551170 is a deficient number, since it is larger than the sum of its proper divisors (68845392758).

81123551170 is a wasteful number, since it uses less digits than its factorization.

81123551170 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 219252885.

The product of its (nonzero) digits is 8400, while the sum is 34.

The spelling of 81123551170 in words is "eighty-one billion, one hundred twenty-three million, five hundred fifty-one thousand, one hundred seventy".