21235132543 has 4 divisors (see below), whose sum is σ = 21236724000. Its totient is φ = 21233541088.

The previous prime is 21235132517. The next prime is 21235132561. The reversal of 21235132543 is 34523153212.

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

It is a cyclic number.

It is not a de Polignac number, because 21235132543 - 2⁵ = 21235132511 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21235132573) 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, 775543 + ... + 802456.

It is an arithmetic number, because the mean of its divisors is an integer number (5309181000).

Almost surely, 2^21235132543 is an apocalyptic number.

21235132543 is a deficient number, since it is larger than the sum of its proper divisors (1591457).

21235132543 is a wasteful number, since it uses less digits than its factorization.

21235132543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1591456.

The product of its digits is 21600, while the sum is 31.

Adding to 21235132543 its reverse (34523153212), we get a palindrome (55758285755).

The spelling of 21235132543 in words is "twenty-one billion, two hundred thirty-five million, one hundred thirty-two thousand, five hundred forty-three".