81828880 has 80 divisors (see below), whose sum is σ = 222128640. Its totient is φ = 27449856.

The previous prime is 81828869. The next prime is 81828881. The reversal of 81828880 is 8882818.

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (81828881) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24766 + ... + 27874.

It is an arithmetic number, because the mean of its divisors is an integer number (2776608).

Almost surely, 2^81828880 is an apocalyptic number.

81828880 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 81828880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (111064320).

81828880 is an abundant number, since it is smaller than the sum of its proper divisors (140299760).

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

81828880 is a wasteful number, since it uses less digits than its factorization.

81828880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3176 (or 3170 counting only the distinct ones).

The product of its (nonzero) digits is 65536, while the sum is 43.

The square root of 81828880 is about 9045.9316822536. The cubic root of 81828880 is about 434.1457317444.

The spelling of 81828880 in words is "eighty-one million, eight hundred twenty-eight thousand, eight hundred eighty".