21043541203 has 4 divisors (see below), whose sum is σ = 21297077928. Its totient is φ = 20790004480.

The previous prime is 21043541177. The next prime is 21043541213. The reversal of 21043541203 is 30214534012.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21043541203 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21043541213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 126768238 + ... + 126768403.

It is an arithmetic number, because the mean of its divisors is an integer number (5324269482).

Almost surely, 2^21043541203 is an apocalyptic number.

21043541203 is a deficient number, since it is larger than the sum of its proper divisors (253536725).

21043541203 is an equidigital number, since it uses as much as digits as its factorization.

21043541203 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 253536724.

The product of its (nonzero) digits is 2880, while the sum is 25.

The spelling of 21043541203 in words is "twenty-one billion, forty-three million, five hundred forty-one thousand, two hundred three".