1644100216512 has 168 divisors, whose sum is σ = 4730962130640. Its totient is φ = 503665643520.

The previous prime is 1644100216501. The next prime is 1644100216513. The reversal of 1644100216512 is 2156120014461.

It is a super-3 number, since 3×1644100216512³ (a number of 38 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (1644100216513) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7319962 + ... + 7541222.

Almost surely, 2^{1644100216512} is an apocalyptic number.

1644100216512 is a gapful number since it is divisible by the number (12) 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 1644100216512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2365481065320).

1644100216512 is an abundant number, since it is smaller than the sum of its proper divisors (3086861914128).

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

1644100216512 is a wasteful number, since it uses less digits than its factorization.

1644100216512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221531 (or 221508 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 33.

The spelling of 1644100216512 in words is "one trillion, six hundred forty-four billion, one hundred million, two hundred sixteen thousand, five hundred twelve".