817680440 has 16 divisors (see below), whose sum is σ = 1839781080. Its totient is φ = 327072160.

The previous prime is 817680439. The next prime is 817680463. The reversal of 817680440 is 44086718.

It is a junction number, because it is equal to n+sod(n) for n = 817680394 and 817680403.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 10220966 + ... + 10221045.

Almost surely, 2^817680440 is an apocalyptic number.

It is an amenable number.

817680440 is an abundant number, since it is smaller than the sum of its proper divisors (1022100640).

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

817680440 is a wasteful number, since it uses less digits than its factorization.

817680440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20442022 (or 20442018 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 38.

The square root of 817680440 is about 28595.1121697398. The cubic root of 817680440 is about 935.1067738168.

The spelling of 817680440 in words is "eight hundred seventeen million, six hundred eighty thousand, four hundred forty".