21300305353 has 2 divisors, whose sum is σ = 21300305354. Its totient is φ = 21300305352.

The previous prime is 21300305347. The next prime is 21300305399. The reversal of 21300305353 is 35350300312.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21186840249 + 113465104 = 145557^2 + 10652^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21300305353 is a prime.

It is not a weakly prime, because it can be changed into another prime (21300305333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10650152676 + 10650152677.

It is an arithmetic number, because the mean of its divisors is an integer number (10650152677).

Almost surely, 2^21300305353 is an apocalyptic number.

It is an amenable number.

21300305353 is a deficient number, since it is larger than the sum of its proper divisors (1).

21300305353 is an equidigital number, since it uses as much as digits as its factorization.

21300305353 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4050, while the sum is 25.

Adding to 21300305353 its reverse (35350300312), we get a palindrome (56650605665).

The spelling of 21300305353 in words is "twenty-one billion, three hundred million, three hundred five thousand, three hundred fifty-three".