21031270553 has 2 divisors, whose sum is σ = 21031270554. Its totient is φ = 21031270552.

The previous prime is 21031270523. The next prime is 21031270591. The reversal of 21031270553 is 35507213012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16020471184 + 5010799369 = 126572^2 + 70787^2 .

It is a cyclic number.

It is not a de Polignac number, because 21031270553 - 2¹⁸ = 21031008409 is a prime.

It is not a weakly prime, because it can be changed into another prime (21031270523) 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, 10515635276 + 10515635277.

It is an arithmetic number, because the mean of its divisors is an integer number (10515635277).

Almost surely, 2^21031270553 is an apocalyptic number.

It is an amenable number.

21031270553 is a deficient number, since it is larger than the sum of its proper divisors (1).

21031270553 is an equidigital number, since it uses as much as digits as its factorization.

21031270553 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6300, while the sum is 29.

Adding to 21031270553 its reverse (35507213012), we get a palindrome (56538483565).

The spelling of 21031270553 in words is "twenty-one billion, thirty-one million, two hundred seventy thousand, five hundred fifty-three".