21144303353 has 2 divisors, whose sum is σ = 21144303354. Its totient is φ = 21144303352.

The previous prime is 21144303337. The next prime is 21144303359. The reversal of 21144303353 is 35330344112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20156332729 + 987970624 = 141973^2 + 31432^2 .

It is a cyclic number.

It is not a de Polignac number, because 21144303353 - 2⁴ = 21144303337 is a prime.

It is not a weakly prime, because it can be changed into another prime (21144303359) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10572151676 + 10572151677.

It is an arithmetic number, because the mean of its divisors is an integer number (10572151677).

Almost surely, 2^21144303353 is an apocalyptic number.

It is an amenable number.

21144303353 is a deficient number, since it is larger than the sum of its proper divisors (1).

21144303353 is an equidigital number, since it uses as much as digits as its factorization.

21144303353 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12960, while the sum is 29.

Adding to 21144303353 its reverse (35330344112), we get a palindrome (56474647465).

The spelling of 21144303353 in words is "twenty-one billion, one hundred forty-four million, three hundred three thousand, three hundred fifty-three".