21343467641 has 2 divisors, whose sum is σ = 21343467642. Its totient is φ = 21343467640.

The previous prime is 21343467599. The next prime is 21343467643. The reversal of 21343467641 is 14676434312.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21267847225 + 75620416 = 145835^2 + 8696^2 .

It is a cyclic number.

It is not a de Polignac number, because 21343467641 - 2¹⁴ = 21343451257 is a prime.

It is a super-2 number, since 2×21343467641² (a number of 21 digits) contains 22 as substring.

Together with 21343467643, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21343467643) 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 as a sum of consecutive naturals, namely, 10671733820 + 10671733821.

It is an arithmetic number, because the mean of its divisors is an integer number (10671733821).

Almost surely, 2^21343467641 is an apocalyptic number.

It is an amenable number.

21343467641 is a deficient number, since it is larger than the sum of its proper divisors (1).

21343467641 is an equidigital number, since it uses as much as digits as its factorization.

21343467641 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 290304, while the sum is 41.

The spelling of 21343467641 in words is "twenty-one billion, three hundred forty-three million, four hundred sixty-seven thousand, six hundred forty-one".