81480816 has 120 divisors (see below), whose sum is σ = 249150720. Its totient is φ = 25707456.

The previous prime is 81480793. The next prime is 81480857. The reversal of 81480816 is 61808418.

It is a Harshad number since it is a multiple of its sum of digits (36).

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 23 ways as a sum of consecutive naturals, for example, 73321 + ... + 74423.

It is an arithmetic number, because the mean of its divisors is an integer number (2076256).

Almost surely, 2^81480816 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 81480816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124575360).

81480816 is an abundant number, since it is smaller than the sum of its proper divisors (167669904).

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

81480816 is a wasteful number, since it uses less digits than its factorization.

81480816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1145 (or 1127 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 36.

The square root of 81480816 is about 9026.6724766106. The cubic root of 81480816 is about 433.5293020267.

The spelling of 81480816 in words is "eighty-one million, four hundred eighty thousand, eight hundred sixteen".