543221921 has 4 divisors (see below), whose sum is σ = 592605744. Its totient is φ = 493838100.

The previous prime is 543221873. The next prime is 543221929. The reversal of 543221921 is 129122345.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 543221921 - 2¹⁰ = 543220897 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (543221929) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24691895 + ... + 24691916.

It is an arithmetic number, because the mean of its divisors is an integer number (148151436).

Almost surely, 2^543221921 is an apocalyptic number.

It is an amenable number.

543221921 is a deficient number, since it is larger than the sum of its proper divisors (49383823).

543221921 is a wasteful number, since it uses less digits than its factorization.

543221921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49383822.

The product of its digits is 4320, while the sum is 29.

The square root of 543221921 is about 23307.1216798643. The cubic root of 543221921 is about 815.9416373619.

The spelling of 543221921 in words is "five hundred forty-three million, two hundred twenty-one thousand, nine hundred twenty-one".