21034729253 has 2 divisors, whose sum is σ = 21034729254. Its totient is φ = 21034729252.

The previous prime is 21034729237. The next prime is 21034729273. The reversal of 21034729253 is 35292743012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12426229729 + 8608499524 = 111473^2 + 92782^2 .

It is a cyclic number.

It is not a de Polignac number, because 21034729253 - 2⁴ = 21034729237 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21034729213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10517364626 + 10517364627.

It is an arithmetic number, because the mean of its divisors is an integer number (10517364627).

Almost surely, 2^21034729253 is an apocalyptic number.

It is an amenable number.

21034729253 is a deficient number, since it is larger than the sum of its proper divisors (1).

21034729253 is an equidigital number, since it uses as much as digits as its factorization.

21034729253 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 90720, while the sum is 38.

The spelling of 21034729253 in words is "twenty-one billion, thirty-four million, seven hundred twenty-nine thousand, two hundred fifty-three".