1643443 has 8 divisors (see below), whose sum is σ = 1757120. Its totient is φ = 1532520.

The previous prime is 1643431. The next prime is 1643461. The reversal of 1643443 is 3443461.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1643443 is a prime.

It is a d-powerful number, because it can be written as 1 + 6³ + 4³ + 3¹⁰ + 4⁶ + 4¹⁰ + 3¹² .

1643443 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1643423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 628 + ... + 1918.

It is an arithmetic number, because the mean of its divisors is an integer number (219640).

2^1643443 is an apocalyptic number.

1643443 is a deficient number, since it is larger than the sum of its proper divisors (113677).

1643443 is a wasteful number, since it uses less digits than its factorization.

1643443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1377.

The product of its digits is 3456, while the sum is 25.

The square root of 1643443 is about 1281.9684083471. The cubic root of 1643443 is about 118.0098383064.

The spelling of 1643443 in words is "one million, six hundred forty-three thousand, four hundred forty-three".