1644768471168 has 128 divisors (see below), whose sum is σ = 4863231480000. Its totient is φ = 547253231616.

The previous prime is 1644768471113. The next prime is 1644768471173. The reversal of 1644768471168 is 8611748674461.

1644768471168 is a `hidden beast` number, since 1 + 6 + 4 + 47 + 68 + 471 + 1 + 68 = 666.

It is a tau number, because it is divible by the number of its divisors (128).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1455408 + ... + 2325456.

Almost surely, 2^{1644768471168} is an apocalyptic number.

1644768471168 is a gapful number since it is divisible by the number (18) 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 1644768471168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2431615740000).

1644768471168 is an abundant number, since it is smaller than the sum of its proper divisors (3218463008832).

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

1644768471168 is an equidigital number, since it uses as much as digits as its factorization.

1644768471168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 870619 (or 870601 counting only the distinct ones).

The product of its digits is 43352064, while the sum is 63.

The spelling of 1644768471168 in words is "one trillion, six hundred forty-four billion, seven hundred sixty-eight million, four hundred seventy-one thousand, one hundred sixty-eight".