1644585667396 has 81 divisors (see below), whose sum is σ = 3377290333599. Its totient is φ = 698689925136.

The previous prime is 1644585667339. The next prime is 1644585667421. The reversal of 1644585667396 is 6937665854461.

The square root of 1644585667396 is 1282414.

It is a perfect power (a square), and thus also a powerful number.

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 26 ways as a sum of consecutive naturals, for example, 2495577315 + ... + 2495577973.

Almost surely, 2^{1644585667396} is an apocalyptic number.

1644585667396 is the 1282414-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1644585667396

1644585667396 is an abundant number, since it is smaller than the sum of its proper divisors (1732704666203).

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

1644585667396 is an frugal number, since it uses more digits than its factorization.

1644585667396 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1614 (or 807 counting only the distinct ones).

The product of its digits is 783820800, while the sum is 70.

The spelling of 1644585667396 in words is "one trillion, six hundred forty-four billion, five hundred eighty-five million, six hundred sixty-seven thousand, three hundred ninety-six".