809081400 has 96 divisors (see below), whose sum is σ = 2589120000. Its totient is φ = 208790400.

The previous prime is 809081393. The next prime is 809081401. The reversal of 809081400 is 4180908.

It is a happy number.

It is a super-2 number, since 2×809081400² = 1309225423651920000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (809081401) by changing a digit.

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, 3150 + ... + 40349.

It is an arithmetic number, because the mean of its divisors is an integer number (26970000).

Almost surely, 2^809081400 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 809081400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1294560000).

809081400 is an abundant number, since it is smaller than the sum of its proper divisors (1780038600).

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

809081400 is a wasteful number, since it uses less digits than its factorization.

809081400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43549 (or 43540 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 30.

The square root of 809081400 is about 28444.3562064604. The cubic root of 809081400 is about 931.8172353099.

The spelling of 809081400 in words is "eight hundred nine million, eighty-one thousand, four hundred".