809555040 has 384 divisors, whose sum is σ = 3411072000. Its totient is φ = 175177728.

The previous prime is 809555029. The next prime is 809555063. The reversal of 809555040 is 40555908.

It is a happy number.

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

It is a junction number, because it is equal to n+sod(n) for n = 809554986 and 809555004.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 573856 + ... + 575264.

It is an arithmetic number, because the mean of its divisors is an integer number (8883000).

Almost surely, 2^809555040 is an apocalyptic number.

809555040 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 809555040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1705536000).

809555040 is an abundant number, since it is smaller than the sum of its proper divisors (2601516960).

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

809555040 is a wasteful number, since it uses less digits than its factorization.

809555040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1459 (or 1445 counting only the distinct ones).

The product of its (nonzero) digits is 36000, while the sum is 36.

The square root of 809555040 is about 28452.6807172892. The cubic root of 809555040 is about 931.9990298823. Note that the first 3 decimals are identical.

The spelling of 809555040 in words is "eight hundred nine million, five hundred fifty-five thousand, forty".