81875556 has 48 divisors (see below), whose sum is σ = 242596480. Its totient is φ = 23392800.

The previous prime is 81875543. The next prime is 81875597. The reversal of 81875556 is 65557818.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53395 + ... + 54906.

Almost surely, 2^81875556 is an apocalyptic number.

It is an amenable number.

81875556 is an abundant number, since it is smaller than the sum of its proper divisors (160720924).

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

81875556 is a wasteful number, since it uses less digits than its factorization.

81875556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108321 (or 108313 counting only the distinct ones).

The product of its digits is 336000, while the sum is 45.

The square root of 81875556 is about 9048.5112587652. The cubic root of 81875556 is about 434.2282630562.

The spelling of 81875556 in words is "eighty-one million, eight hundred seventy-five thousand, five hundred fifty-six".