81998104 has 16 divisors (see below), whose sum is σ = 153895320. Its totient is φ = 40959360.

The previous prime is 81998071. The next prime is 81998143. The reversal of 81998104 is 40189918.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 4992 + ... + 13744.

Almost surely, 2^81998104 is an apocalyptic number.

It is an amenable number.

81998104 is a deficient number, since it is larger than the sum of its proper divisors (71897216).

81998104 is a wasteful number, since it uses less digits than its factorization.

81998104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9930 (or 9926 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 40.

The square root of 81998104 is about 9055.2804484455. The cubic root of 81998104 is about 434.4448001214. Note that the first 3 decimals are identical.

The spelling of 81998104 in words is "eighty-one million, nine hundred ninety-eight thousand, one hundred four".