21543410201 has 4 divisors (see below), whose sum is σ = 21545560272. Its totient is φ = 21541260132.

The previous prime is 21543410179. The next prime is 21543410219. The reversal of 21543410201 is 10201434512.

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 21543410201 - 2¹⁰ = 21543409177 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21543410501) 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, 1059935 + ... + 1080068.

It is an arithmetic number, because the mean of its divisors is an integer number (5386390068).

Almost surely, 2^21543410201 is an apocalyptic number.

It is an amenable number.

21543410201 is a deficient number, since it is larger than the sum of its proper divisors (2150071).

21543410201 is a wasteful number, since it uses less digits than its factorization.

21543410201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2150070.

The product of its (nonzero) digits is 960, while the sum is 23.

Adding to 21543410201 its reverse (10201434512), we get a palindrome (31744844713).

The spelling of 21543410201 in words is "twenty-one billion, five hundred forty-three million, four hundred ten thousand, two hundred one".