21043541231 has 2 divisors, whose sum is σ = 21043541232. Its totient is φ = 21043541230.

The previous prime is 21043541213. The next prime is 21043541263. The reversal of 21043541231 is 13214534012.

It is a happy number.

Together with previous prime (21043541213) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21043541231 - 2³⁴ = 3863672047 is a prime.

It is a super-2 number, since 2×21043541231² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21043541231.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21043546231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10521770615 + 10521770616.

It is an arithmetic number, because the mean of its divisors is an integer number (10521770616).

Almost surely, 2^21043541231 is an apocalyptic number.

21043541231 is a deficient number, since it is larger than the sum of its proper divisors (1).

21043541231 is an equidigital number, since it uses as much as digits as its factorization.

21043541231 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2880, while the sum is 26.

The spelling of 21043541231 in words is "twenty-one billion, forty-three million, five hundred forty-one thousand, two hundred thirty-one".