21554114161 has 2 divisors, whose sum is σ = 21554114162. Its totient is φ = 21554114160.

The previous prime is 21554114129. The next prime is 21554114221. The reversal of 21554114161 is 16141145512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11278440000 + 10275674161 = 106200^2 + 101369^2 .

It is a cyclic number.

It is not a de Polignac number, because 21554114161 - 2⁵ = 21554114129 is a prime.

It is not a weakly prime, because it can be changed into another prime (21554114261) 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, 10777057080 + 10777057081.

It is an arithmetic number, because the mean of its divisors is an integer number (10777057081).

Almost surely, 2^21554114161 is an apocalyptic number.

It is an amenable number.

21554114161 is a deficient number, since it is larger than the sum of its proper divisors (1).

21554114161 is an equidigital number, since it uses as much as digits as its factorization.

21554114161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4800, while the sum is 31.

Adding to 21554114161 its reverse (16141145512), we get a palindrome (37695259673).

The spelling of 21554114161 in words is "twenty-one billion, five hundred fifty-four million, one hundred fourteen thousand, one hundred sixty-one".