1663041851856 has 720 divisors, whose sum is σ = 6170282576640. Its totient is φ = 408474316800.

The previous prime is 1663041851843. The next prime is 1663041851857. The reversal of 1663041851856 is 6581581403661.

1663041851856 is a `hidden beast` number, since 1 + 6 + 6 + 30 + 41 + 8 + 518 + 56 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1663041851857) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 249665166 + ... + 249671826.

It is an arithmetic number, because the mean of its divisors is an integer number (8569836912).

Almost surely, 2^{1663041851856} is an apocalyptic number.

1663041851856 is a gapful number since it is divisible by the number (16) 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 1663041851856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3085141288320).

1663041851856 is an abundant number, since it is smaller than the sum of its proper divisors (4507240724784).

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

1663041851856 is a wasteful number, since it uses less digits than its factorization.

1663041851856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6816 (or 6796 counting only the distinct ones).

The product of its (nonzero) digits is 4147200, while the sum is 54.

The spelling of 1663041851856 in words is "one trillion, six hundred sixty-three billion, forty-one million, eight hundred fifty-one thousand, eight hundred fifty-six".