4021543 has 2 divisors, whose sum is σ = 4021544. Its totient is φ = 4021542.

The previous prime is 4021531. The next prime is 4021561. The reversal of 4021543 is 3451204.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-4021543 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 4021543.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4021513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2010771 + 2010772.

It is an arithmetic number, because the mean of its divisors is an integer number (2010772).

Almost surely, 2^4021543 is an apocalyptic number.

4021543 is a deficient number, since it is larger than the sum of its proper divisors (1).

4021543 is an equidigital number, since it uses as much as digits as its factorization.

4021543 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 480, while the sum is 19.

The square root of 4021543 is about 2005.3785178863. The cubic root of 4021543 is about 159.0245732889.

Adding to 4021543 its reverse (3451204), we get a palindrome (7472747).

The spelling of 4021543 in words is "four million, twenty-one thousand, five hundred forty-three".