1985855454408 has 256 divisors, whose sum is σ = 6260626391040. Its totient is φ = 512399923200.

The previous prime is 1985855454379. The next prime is 1985855454421. The reversal of 1985855454408 is 8044545585891.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4708966 + ... + 5113322.

It is an arithmetic number, because the mean of its divisors is an integer number (24455571840).

Almost surely, 2^{1985855454408} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1985855454408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3130313195520).

1985855454408 is an abundant number, since it is smaller than the sum of its proper divisors (4274770936632).

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

1985855454408 is a wasteful number, since it uses less digits than its factorization.

1985855454408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 404468 (or 404464 counting only the distinct ones).

The product of its (nonzero) digits is 184320000, while the sum is 66.

The spelling of 1985855454408 in words is "one trillion, nine hundred eighty-five billion, eight hundred fifty-five million, four hundred fifty-four thousand, four hundred eight".