21343133081 has 2 divisors, whose sum is σ = 21343133082. Its totient is φ = 21343133080.

The previous prime is 21343133057. The next prime is 21343133099. The reversal of 21343133081 is 18033134312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16573987600 + 4769145481 = 128740^2 + 69059^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21343133081 is a prime.

It is a super-2 number, since 2×21343133081² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21303133081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10671566540 + 10671566541.

It is an arithmetic number, because the mean of its divisors is an integer number (10671566541).

Almost surely, 2^21343133081 is an apocalyptic number.

It is an amenable number.

21343133081 is a deficient number, since it is larger than the sum of its proper divisors (1).

21343133081 is an equidigital number, since it uses as much as digits as its factorization.

21343133081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5184, while the sum is 29.

Adding to 21343133081 its reverse (18033134312), we get a palindrome (39376267393).

The spelling of 21343133081 in words is "twenty-one billion, three hundred forty-three million, one hundred thirty-three thousand, eighty-one".