81334100 has 36 divisors (see below), whose sum is σ = 177321984. Its totient is φ = 32381280.

The previous prime is 81334093. The next prime is 81334129. The reversal of 81334100 is 143318.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20909 + ... + 24491.

Almost surely, 2^81334100 is an apocalyptic number.

It is an amenable number.

81334100 is an abundant number, since it is smaller than the sum of its proper divisors (95987884).

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

81334100 is a wasteful number, since it uses less digits than its factorization.

81334100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3824 (or 3817 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 81334100 is about 9018.5420107687. The cubic root of 81334100 is about 433.2689384917.

Adding to 81334100 its reverse (143318), we get a palindrome (81477418).

The spelling of 81334100 in words is "eighty-one million, three hundred thirty-four thousand, one hundred".