21242240043 has 4 divisors (see below), whose sum is σ = 28322986728. Its totient is φ = 14161493360.

The previous prime is 21242240011. The next prime is 21242240059. The reversal of 21242240043 is 34004224212.

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 21242240043 - 2⁵ = 21242240011 is a prime.

It is a super-4 number, since 4×21242240043⁴ (a number of 42 digits) contains 4444 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21242239995 and 21242240022.

It is not an unprimeable number, because it can be changed into a prime (21242240543) 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 in 3 ways as a sum of consecutive naturals, for example, 3540373338 + ... + 3540373343.

It is an arithmetic number, because the mean of its divisors is an integer number (7080746682).

Almost surely, 2^21242240043 is an apocalyptic number.

21242240043 is a deficient number, since it is larger than the sum of its proper divisors (7080746685).

21242240043 is an equidigital number, since it uses as much as digits as its factorization.

21242240043 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7080746684.

The product of its (nonzero) digits is 3072, while the sum is 24.

Adding to 21242240043 its reverse (34004224212), we get a palindrome (55246464255).

The spelling of 21242240043 in words is "twenty-one billion, two hundred forty-two million, two hundred forty thousand, forty-three".