1643485541 has 16 divisors (see below), whose sum is σ = 1754596800. Its totient is φ = 1534982400.

The previous prime is 1643485531. The next prime is 1643485567. The reversal of 1643485541 is 1455843461.

It is a cyclic number.

It is not a de Polignac number, because 1643485541 - 2²⁶ = 1576376677 is a prime.

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1643485531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 435101 + ... + 438861.

It is an arithmetic number, because the mean of its divisors is an integer number (109662300).

Almost surely, 2^1643485541 is an apocalyptic number.

It is an amenable number.

1643485541 is a deficient number, since it is larger than the sum of its proper divisors (111111259).

1643485541 is a wasteful number, since it uses less digits than its factorization.

1643485541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4100.

The product of its digits is 230400, while the sum is 41.

The square root of 1643485541 is about 40539.9252712681. The cubic root of 1643485541 is about 1180.1085653727.

The spelling of 1643485541 in words is "one billion, six hundred forty-three million, four hundred eighty-five thousand, five hundred forty-one".