81801112 has 32 divisors (see below), whose sum is σ = 160282800. Its totient is φ = 39088000.

The previous prime is 81801107. The next prime is 81801143. The reversal of 81801112 is 21110818.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21687 + ... + 25177.

Almost surely, 2^81801112 is an apocalyptic number.

It is an amenable number.

81801112 is a deficient number, since it is larger than the sum of its proper divisors (78481688).

81801112 is a wasteful number, since it uses less digits than its factorization.

81801112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3627 (or 3623 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 22.

The square root of 81801112 is about 9044.3967184108. The cubic root of 81801112 is about 434.0966181855.

The spelling of 81801112 in words is "eighty-one million, eight hundred one thousand, one hundred twelve".