21533423055541 has 2 divisors, whose sum is σ = 21533423055542. Its totient is φ = 21533423055540.

The previous prime is 21533423055479. The next prime is 21533423055553. The reversal of 21533423055541 is 14555032433512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12225889874916 + 9307533180625 = 3496554^2 + 3050825^2 .

It is a cyclic number.

It is not a de Polignac number, because 21533423055541 - 2²⁷ = 21533288837813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21533423055841) 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, 10766711527770 + 10766711527771.

It is an arithmetic number, because the mean of its divisors is an integer number (10766711527771).

Almost surely, 2^{21533423055541} is an apocalyptic number.

It is an amenable number.

21533423055541 is a deficient number, since it is larger than the sum of its proper divisors (1).

21533423055541 is an equidigital number, since it uses as much as digits as its factorization.

21533423055541 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1080000, while the sum is 43.

The spelling of 21533423055541 in words is "twenty-one trillion, five hundred thirty-three billion, four hundred twenty-three million, fifty-five thousand, five hundred forty-one".