81830784 has 96 divisors (see below), whose sum is σ = 252909000. Its totient is φ = 23374848.

The previous prime is 81830773. The next prime is 81830789. The reversal of 81830784 is 48703818.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81830789) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16642 + ... + 20990.

Almost surely, 2^81830784 is an apocalyptic number.

81830784 is a gapful number since it is divisible by the number (84) 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 81830784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (126454500).

81830784 is an abundant number, since it is smaller than the sum of its proper divisors (171078216).

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

81830784 is a wasteful number, since it uses less digits than its factorization.

81830784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4380 (or 4361 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 39.

The square root of 81830784 is about 9046.0369223213. The cubic root of 81830784 is about 434.1490989626.

The spelling of 81830784 in words is "eighty-one million, eight hundred thirty thousand, seven hundred eighty-four".