21043121241 has 4 divisors (see below), whose sum is σ = 28057494992. Its totient is φ = 14028747492.

The previous prime is 21043121221. The next prime is 21043121287. The reversal of 21043121241 is 14212134012.

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 not a de Polignac number, because 21043121241 - 2¹⁴ = 21043104857 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21043121221) 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, 3507186871 + ... + 3507186876.

It is an arithmetic number, because the mean of its divisors is an integer number (7014373748).

Almost surely, 2^21043121241 is an apocalyptic number.

It is an amenable number.

21043121241 is a deficient number, since it is larger than the sum of its proper divisors (7014373751).

21043121241 is an equidigital number, since it uses as much as digits as its factorization.

21043121241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7014373750.

The product of its (nonzero) digits is 384, while the sum is 21.

Adding to 21043121241 its reverse (14212134012), we get a palindrome (35255255253).

The spelling of 21043121241 in words is "twenty-one billion, forty-three million, one hundred twenty-one thousand, two hundred forty-one".