81830400 has 120 divisors (see below), whose sum is σ = 270448464. Its totient is φ = 21811200.

The previous prime is 81830377. The next prime is 81830423. The reversal of 81830400 is 403818.

It is an interprime number because it is at equal distance from previous prime (81830377) and next prime (81830423).

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 37335 + ... + 39465.

Almost surely, 2^81830400 is an apocalyptic number.

81830400 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 81830400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (135224232).

81830400 is an abundant number, since it is smaller than the sum of its proper divisors (188618064).

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

81830400 is a wasteful number, since it uses less digits than its factorization.

81830400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2162 (or 2141 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 24.

The square root of 81830400 is about 9046.0156975323. The cubic root of 81830400 is about 434.1484198639.

The spelling of 81830400 in words is "eighty-one million, eight hundred thirty thousand, four hundred".