21004305053 has 2 divisors, whose sum is σ = 21004305054. Its totient is φ = 21004305052.

The previous prime is 21004305031. The next prime is 21004305059. The reversal of 21004305053 is 35050340012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20363860804 + 640444249 = 142702^2 + 25307^2 .

It is a cyclic number.

It is not a de Polignac number, because 21004305053 - 2⁶ = 21004304989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21004305059) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10502152526 + 10502152527.

It is an arithmetic number, because the mean of its divisors is an integer number (10502152527).

Almost surely, 2^21004305053 is an apocalyptic number.

It is an amenable number.

21004305053 is a deficient number, since it is larger than the sum of its proper divisors (1).

21004305053 is an equidigital number, since it uses as much as digits as its factorization.

21004305053 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1800, while the sum is 23.

Adding to 21004305053 its reverse (35050340012), we get a palindrome (56054645065).

The spelling of 21004305053 in words is "twenty-one billion, four million, three hundred five thousand, fifty-three".