1685861398100 has 144 divisors (see below), whose sum is σ = 4101909336000. Its totient is φ = 596213376000.

The previous prime is 1685861398087. The next prime is 1685861398159. The reversal of 1685861398100 is 18931685861.

It is a super-2 number, since 2×1685861398100² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5830751 + ... + 6113049.

It is an arithmetic number, because the mean of its divisors is an integer number (28485481500).

Almost surely, 2^{1685861398100} is an apocalyptic number.

1685861398100 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 1685861398100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2050954668000).

1685861398100 is an abundant number, since it is smaller than the sum of its proper divisors (2416047937900).

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

1685861398100 is a wasteful number, since it uses less digits than its factorization.

1685861398100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 282474 (or 282467 counting only the distinct ones).

The product of its (nonzero) digits is 2488320, while the sum is 56.

The spelling of 1685861398100 in words is "one trillion, six hundred eighty-five billion, eight hundred sixty-one million, three hundred ninety-eight thousand, one hundred".