213543643 has 2 divisors, whose sum is σ = 213543644. Its totient is φ = 213543642.

The previous prime is 213543637. The next prime is 213543727. The reversal of 213543643 is 346345312.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-213543643 is a prime.

It is a super-3 number, since 3×213543643³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is equal to p_11786332 and since 213543643 and 11786332 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (213543623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106771821 + 106771822.

It is an arithmetic number, because the mean of its divisors is an integer number (106771822).

Almost surely, 2^213543643 is an apocalyptic number.

213543643 is a deficient number, since it is larger than the sum of its proper divisors (1).

213543643 is an equidigital number, since it uses as much as digits as its factorization.

213543643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25920, while the sum is 31.

The square root of 213543643 is about 14613.1325526049. The cubic root of 213543643 is about 597.7169189576.

Adding to 213543643 its reverse (346345312), we get a palindrome (559888955).

The spelling of 213543643 in words is "two hundred thirteen million, five hundred forty-three thousand, six hundred forty-three".