21543225241 has 4 divisors (see below), whose sum is σ = 22479887232. Its totient is φ = 20606563252.

The previous prime is 21543225239. The next prime is 21543225289. The reversal of 21543225241 is 14252234512.

It is a happy number.

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 21543225241 - 2¹ = 21543225239 is a prime.

It is a super-2 number, since 2×21543225241² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21543220241) 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, 468330961 + ... + 468331006.

It is an arithmetic number, because the mean of its divisors is an integer number (5619971808).

Almost surely, 2^21543225241 is an apocalyptic number.

It is an amenable number.

21543225241 is a deficient number, since it is larger than the sum of its proper divisors (936661991).

21543225241 is an equidigital number, since it uses as much as digits as its factorization.

21543225241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 936661990.

The product of its digits is 19200, while the sum is 31.

Adding to 21543225241 its reverse (14252234512), we get a palindrome (35795459753).

The spelling of 21543225241 in words is "twenty-one billion, five hundred forty-three million, two hundred twenty-five thousand, two hundred forty-one".