1644786680832 has 704 divisors, whose sum is σ = 5413213877760. Its totient is φ = 490705256448.

The previous prime is 1644786680773. The next prime is 1644786680843. The reversal of 1644786680832 is 2380866874461.

1644786680832 is a `hidden beast` number, since 1 + 6 + 4 + 478 + 6 + 6 + 80 + 83 + 2 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 1644786680832.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2518815418 + ... + 2518816070.

Almost surely, 2^{1644786680832} is an apocalyptic number.

1644786680832 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 1644786680832, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2706606938880).

1644786680832 is an abundant number, since it is smaller than the sum of its proper divisors (3768427196928).

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

1644786680832 is a wasteful number, since it uses less digits than its factorization.

1644786680832 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 955 (or 931 counting only the distinct ones).

The product of its (nonzero) digits is 74317824, while the sum is 63.

The spelling of 1644786680832 in words is "one trillion, six hundred forty-four billion, seven hundred eighty-six million, six hundred eighty thousand, eight hundred thirty-two".