809431920 has 480 divisors, whose sum is σ = 3245625600. Its totient is φ = 184757760.

The previous prime is 809431919. The next prime is 809431927. The reversal of 809431920 is 29134908.

It is a super-2 number, since 2×809431920² = 1310360066229772800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (809431927) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 4965759 + ... + 4965921.

It is an arithmetic number, because the mean of its divisors is an integer number (6761720).

Almost surely, 2^809431920 is an apocalyptic number.

809431920 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 809431920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1622812800).

809431920 is an abundant number, since it is smaller than the sum of its proper divisors (2436193680).

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

809431920 is a wasteful number, since it uses less digits than its factorization.

809431920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226 (or 203 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 809431920 is about 28450.5170427534. The cubic root of 809431920 is about 931.9517802482.

The spelling of 809431920 in words is "eight hundred nine million, four hundred thirty-one thousand, nine hundred twenty".