521443 has 4 divisors (see below), whose sum is σ = 561568. Its totient is φ = 481320.

The previous prime is 521429. The next prime is 521447. The reversal of 521443 is 344125.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-521443 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 521443.

It is not an unprimeable number, because it can be changed into a prime (521447) 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 3 ways as a sum of consecutive naturals, for example, 20043 + ... + 20068.

It is an arithmetic number, because the mean of its divisors is an integer number (140392).

2⁵²¹⁴⁴³ is an apocalyptic number.

521443 is a deficient number, since it is larger than the sum of its proper divisors (40125).

521443 is a wasteful number, since it uses less digits than its factorization.

521443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40124.

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

The square root of 521443 is about 722.1101024082. The cubic root of 521443 is about 80.4888298995.

Adding to 521443 its reverse (344125), we get a palindrome (865568).

The spelling of 521443 in words is "five hundred twenty-one thousand, four hundred forty-three".