21010221053 has 2 divisors, whose sum is σ = 21010221054. Its totient is φ = 21010221052.

The previous prime is 21010220999. The next prime is 21010221073. The reversal of 21010221053 is 35012201012.

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., 18802442884 + 2207778169 = 137122^2 + 46987^2 .

It is a cyclic number.

It is not a de Polignac number, because 21010221053 - 2²⁰ = 21009172477 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21010221073) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505110526 + 10505110527.

It is an arithmetic number, because the mean of its divisors is an integer number (10505110527).

Almost surely, 2^21010221053 is an apocalyptic number.

It is an amenable number.

21010221053 is a deficient number, since it is larger than the sum of its proper divisors (1).

21010221053 is an equidigital number, since it uses as much as digits as its factorization.

21010221053 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 120, while the sum is 17.

Adding to 21010221053 its reverse (35012201012), we get a palindrome (56022422065).

The spelling of 21010221053 in words is "twenty-one billion, ten million, two hundred twenty-one thousand, fifty-three".