1644368832 has 168 divisors, whose sum is σ = 5015738000. Its totient is φ = 513589248.

The previous prime is 1644368819. The next prime is 1644368897. The reversal of 1644368832 is 2388634461.

It is a super-3 number, since 3×1644368832³ (a number of 29 digits) contains 333 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1060794 + ... + 1062342.

Almost surely, 2^1644368832 is an apocalyptic number.

1644368832 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 1644368832, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2507869000).

1644368832 is an abundant number, since it is smaller than the sum of its proper divisors (3371369168).

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

1644368832 is a wasteful number, since it uses less digits than its factorization.

1644368832 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1683 (or 1670 counting only the distinct ones).

The product of its digits is 663552, while the sum is 45.

The square root of 1644368832 is about 40550.8178955739. The cubic root of 1644368832 is about 1180.3199438855.

The spelling of 1644368832 in words is "one billion, six hundred forty-four million, three hundred sixty-eight thousand, eight hundred thirty-two".