81812024 has 64 divisors (see below), whose sum is σ = 195436800. Its totient is φ = 31256064.

The previous prime is 81811993. The next prime is 81812033. The reversal of 81812024 is 42021818.

81812024 = 2³ + 3³ + ... + 134³.

It is a Cunningham number, because it is equal to 9045²-1.

It is a junction number, because it is equal to n+sod(n) for n = 81811984 and 81812002.

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 15 ways as a sum of consecutive naturals, for example, 15827 + ... + 20349.

It is an arithmetic number, because the mean of its divisors is an integer number (3053700).

Almost surely, 2^81812024 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81812024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (97718400).

81812024 is an abundant number, since it is smaller than the sum of its proper divisors (113624776).

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

81812024 is a wasteful number, since it uses less digits than its factorization.

81812024 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4572 (or 4568 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 26.

The square root of 81812024 is about 9044.9999447208. Note that the first 4 decimals coincide. The cubic root of 81812024 is about 434.1159196822.

The spelling of 81812024 in words is "eighty-one million, eight hundred twelve thousand, twenty-four".