81807376 has 80 divisors (see below), whose sum is σ = 190166400. Its totient is φ = 33352704.

The previous prime is 81807317. The next prime is 81807379. The reversal of 81807376 is 67370818.

It is not an unprimeable number, because it can be changed into a prime (81807379) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 288931 + ... + 289213.

It is an arithmetic number, because the mean of its divisors is an integer number (2377080).

Almost surely, 2^81807376 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 81807376, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95083200).

81807376 is an abundant number, since it is smaller than the sum of its proper divisors (108359024).

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

81807376 is a wasteful number, since it uses less digits than its factorization.

81807376 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 416 (or 410 counting only the distinct ones).

The product of its (nonzero) digits is 56448, while the sum is 40.

The square root of 81807376 is about 9044.7430035353. The cubic root of 81807376 is about 434.1076983601.

The spelling of 81807376 in words is "eighty-one million, eight hundred seven thousand, three hundred seventy-six".