21000131266453 has 2 divisors, whose sum is σ = 21000131266454. Its totient is φ = 21000131266452.

The previous prime is 21000131266441. The next prime is 21000131266501. The reversal of 21000131266453 is 35466213100012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11805154554769 + 9194976711684 = 3435863^2 + 3032322^2 .

It is a cyclic number.

It is not a de Polignac number, because 21000131266453 - 2¹³ = 21000131258261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21000131266853) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500065633226 + 10500065633227.

It is an arithmetic number, because the mean of its divisors is an integer number (10500065633227).

Almost surely, 2^{21000131266453} is an apocalyptic number.

It is an amenable number.

21000131266453 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000131266453 is an equidigital number, since it uses as much as digits as its factorization.

21000131266453 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25920, while the sum is 34.

Adding to 21000131266453 its reverse (35466213100012), we get a palindrome (56466344366465).

The spelling of 21000131266453 in words is "twenty-one trillion, one hundred thirty-one million, two hundred sixty-six thousand, four hundred fifty-three".