817725440 has 256 divisors, whose sum is σ = 2415882240. Its totient is φ = 259522560.

The previous prime is 817725437. The next prime is 817725479. The reversal of 817725440 is 44527718.

It is a tau number, because it is divible by the number of its divisors (256).

It is a junction number, because it is equal to n+sod(n) for n = 817725394 and 817725403.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26378225 + ... + 26378255.

It is an arithmetic number, because the mean of its divisors is an integer number (9437040).

Almost surely, 2^817725440 is an apocalyptic number.

817725440 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 817725440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1207941120).

817725440 is an abundant number, since it is smaller than the sum of its proper divisors (1598156800).

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

817725440 is an equidigital number, since it uses as much as digits as its factorization.

817725440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96 (or 68 counting only the distinct ones).

The product of its (nonzero) digits is 62720, while the sum is 38.

The square root of 817725440 is about 28595.8990066758. The cubic root of 817725440 is about 935.1239276383.

The spelling of 817725440 in words is "eight hundred seventeen million, seven hundred twenty-five thousand, four hundred forty".