21443510455253 has 2 divisors, whose sum is σ = 21443510455254. Its totient is φ = 21443510455252.

The previous prime is 21443510455247. The next prime is 21443510455307. The reversal of 21443510455253 is 35255401534412.

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., 20870488706929 + 573021748324 = 4568423^2 + 756982^2 .

It is a cyclic number.

It is not a de Polignac number, because 21443510455253 - 2¹⁸ = 21443510193109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21443510454253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10721755227626 + 10721755227627.

It is an arithmetic number, because the mean of its divisors is an integer number (10721755227627).

Almost surely, 2^{21443510455253} is an apocalyptic number.

It is an amenable number.

21443510455253 is a deficient number, since it is larger than the sum of its proper divisors (1).

21443510455253 is an equidigital number, since it uses as much as digits as its factorization.

21443510455253 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1440000, while the sum is 44.

Adding to 21443510455253 its reverse (35255401534412), we get a palindrome (56698911989665).

The spelling of 21443510455253 in words is "twenty-one trillion, four hundred forty-three billion, five hundred ten million, four hundred fifty-five thousand, two hundred fifty-three".