1644144541 has 8 divisors (see below), whose sum is σ = 1770985944. Its totient is φ = 1517355840.

The previous prime is 1644144521. The next prime is 1644144583. The reversal of 1644144541 is 1454414461.

It can be written as a sum of positive squares in 4 ways, for example, as 8265625 + 1635878916 = 2875^2 + 40446^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1644144541 - 2²⁵ = 1610590109 is a prime.

It is a super-3 number, since 3×1644144541³ (a number of 29 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a junction number, because it is equal to n+sod(n) for n = 1644144497 and 1644144506.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1644144521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 72111 + ... + 92131.

It is an arithmetic number, because the mean of its divisors is an integer number (221373243).

Almost surely, 2^1644144541 is an apocalyptic number.

It is an amenable number.

1644144541 is a deficient number, since it is larger than the sum of its proper divisors (126841403).

1644144541 is a wasteful number, since it uses less digits than its factorization.

1644144541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26351.

The product of its digits is 30720, while the sum is 34.

The square root of 1644144541 is about 40548.0522466863. The cubic root of 1644144541 is about 1180.2662764493.

The spelling of 1644144541 in words is "one billion, six hundred forty-four million, one hundred forty-four thousand, five hundred forty-one".