21541619153 has 2 divisors, whose sum is σ = 21541619154. Its totient is φ = 21541619152.

The previous prime is 21541619123. The next prime is 21541619191. The reversal of 21541619153 is 35191614512.

It is an a-pointer prime, because the next prime (21541619191) can be obtained adding 21541619153 to its sum of digits (38).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21533508049 + 8111104 = 146743^2 + 2848^2 .

It is a cyclic number.

It is not a de Polignac number, because 21541619153 - 2⁸ = 21541618897 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (21541619123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10770809576 + 10770809577.

It is an arithmetic number, because the mean of its divisors is an integer number (10770809577).

Almost surely, 2^21541619153 is an apocalyptic number.

It is an amenable number.

21541619153 is a deficient number, since it is larger than the sum of its proper divisors (1).

21541619153 is an equidigital number, since it uses as much as digits as its factorization.

21541619153 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32400, while the sum is 38.

The spelling of 21541619153 in words is "twenty-one billion, five hundred forty-one million, six hundred nineteen thousand, one hundred fifty-three".