1644944960 has 56 divisors (see below), whose sum is σ = 4052117880. Its totient is φ = 635285504.

The previous prime is 1644944947. The next prime is 1644945059. The reversal of 1644944960 is 694494461.

It can be written as a sum of positive squares in 4 ways, for example, as 710542336 + 934402624 = 26656^2 + 30568^2 .

It is a hoax number, since the sum of its digits (47) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79349 + ... + 97908.

Almost surely, 2^1644944960 is an apocalyptic number.

1644944960 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1644944960 is an abundant number, since it is smaller than the sum of its proper divisors (2407172920).

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

1644944960 is a wasteful number, since it uses less digits than its factorization.

1644944960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177303 (or 177293 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 47.

The square root of 1644944960 is about 40557.9210512571. The cubic root of 1644944960 is about 1180.4577750811.

The spelling of 1644944960 in words is "one billion, six hundred forty-four million, nine hundred forty-four thousand, nine hundred sixty".