21213004543 has 2 divisors, whose sum is σ = 21213004544. Its totient is φ = 21213004542.

The previous prime is 21213004531. The next prime is 21213004559. The reversal of 21213004543 is 34540031212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21213004543 - 2⁵ = 21213004511 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21213004573) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606502271 + 10606502272.

It is an arithmetic number, because the mean of its divisors is an integer number (10606502272).

Almost surely, 2^21213004543 is an apocalyptic number.

21213004543 is a deficient number, since it is larger than the sum of its proper divisors (1).

21213004543 is an equidigital number, since it uses as much as digits as its factorization.

21213004543 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2880, while the sum is 25.

Adding to 21213004543 its reverse (34540031212), we get a palindrome (55753035755).

The spelling of 21213004543 in words is "twenty-one billion, two hundred thirteen million, four thousand, five hundred forty-three".