1685389217400 has 432 divisors, whose sum is σ = 6871593009840. Its totient is φ = 362570342400.

The previous prime is 1685389217389. The next prime is 1685389217423. The reversal of 1685389217400 is 47129835861.

1685389217400 is a `hidden beast` number, since 1 + 6 + 8 + 5 + 389 + 217 + 40 + 0 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 3409980 + ... + 3872820.

It is a 1-persistent number, because it is pandigital, but 2⋅1685389217400 = 3370778434800 is not.

Almost surely, 2^{1685389217400} is an apocalyptic number.

1685389217400 is a gapful number since it is divisible by the number (10) 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 1685389217400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3435796504920).

1685389217400 is an abundant number, since it is smaller than the sum of its proper divisors (5186203792440).

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

1685389217400 is a wasteful number, since it uses less digits than its factorization.

1685389217400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 462904 (or 462875 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 54.

The spelling of 1685389217400 in words is "one trillion, six hundred eighty-five billion, three hundred eighty-nine million, two hundred seventeen thousand, four hundred".