1644844032 has 132 divisors (see below), whose sum is σ = 5115166420. Its totient is φ = 506068992.

The previous prime is 1644844031. The next prime is 1644844087. The reversal of 1644844032 is 2304484461.

1644844032 is a `hidden beast` number, since 1 + 644 + 8 + 4 + 4 + 0 + 3 + 2 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 410305536 + 1234538496 = 20256^2 + 35136^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1644844031) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 112944 + ... + 126672.

Almost surely, 2^1644844032 is an apocalyptic number.

1644844032 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 1644844032, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2557583210).

1644844032 is an abundant number, since it is smaller than the sum of its proper divisors (3470322388).

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

1644844032 is a wasteful number, since it uses less digits than its factorization.

1644844032 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13768 (or 13747 counting only the distinct ones).

The product of its (nonzero) digits is 73728, while the sum is 36.

The square root of 1644844032 is about 40556.6767869361. The cubic root of 1644844032 is about 1180.4336316838.

The spelling of 1644844032 in words is "one billion, six hundred forty-four million, eight hundred forty-four thousand, thirty-two".