1644383601 has 27 divisors (see below), whose sum is σ = 2764443513. Its totient is φ = 939161160.

The previous prime is 1644383593. The next prime is 1644383621. The reversal of 1644383601 is 1063834461.

It is a happy number.

The square root of 1644383601 is 40551.

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

1644383601 is a `hidden beast` number, since 1 + 6 + 4 + 43 + 8 + 3 + 601 = 666.

It is not a de Polignac number, because 1644383601 - 2³ = 1644383593 is a prime.

It is a super-3 number, since 3×1644383601³ (a number of 29 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (1644383621) by changing a digit.

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 26 ways as a sum of consecutive naturals, for example, 850606 + ... + 852536.

Almost surely, 2^1644383601 is an apocalyptic number.

1644383601 is the 40551-st square number.

1644383601 is the 20276-th centered octagonal number.

It is an amenable number.

1644383601 is a deficient number, since it is larger than the sum of its proper divisors (1120059912).

1644383601 is an frugal number, since it uses more digits than its factorization.

1644383601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3882 (or 1941 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 36.

The cubic root of 1644383601 is about 1180.3234775803.

Multiplying 1644383601 by its sum of digits (36), we get a square (59197809636 = 243306²).

The spelling of 1644383601 in words is "one billion, six hundred forty-four million, three hundred eighty-three thousand, six hundred one".