81473120 has 48 divisors (see below), whose sum is σ = 193179168. Its totient is φ = 32471040.

The previous prime is 81473111. The next prime is 81473131. The reversal of 81473120 is 2137418.

It is a self number, because there is not a number n which added to its sum of digits gives 81473120.

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 7 ways as a sum of consecutive naturals, for example, 53165 + ... + 54675.

It is an arithmetic number, because the mean of its divisors is an integer number (4024566).

Almost surely, 2^81473120 is an apocalyptic number.

81473120 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81473120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96589584).

81473120 is an abundant number, since it is smaller than the sum of its proper divisors (111706048).

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

81473120 is a wasteful number, since it uses less digits than its factorization.

81473120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1863 (or 1855 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 26.

The square root of 81473120 is about 9026.2461743518. The cubic root of 81473120 is about 433.5156524066.

The spelling of 81473120 in words is "eighty-one million, four hundred seventy-three thousand, one hundred twenty".