21223201541 has 2 divisors, whose sum is σ = 21223201542. Its totient is φ = 21223201540.

The previous prime is 21223201537. The next prime is 21223201543. The reversal of 21223201541 is 14510232212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12623421316 + 8599780225 = 112354^2 + 92735^2 .

It is a cyclic number.

It is not a de Polignac number, because 21223201541 - 2² = 21223201537 is a prime.

Together with 21223201543, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21223201543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10611600770 + 10611600771.

It is an arithmetic number, because the mean of its divisors is an integer number (10611600771).

Almost surely, 2^21223201541 is an apocalyptic number.

It is an amenable number.

21223201541 is a deficient number, since it is larger than the sum of its proper divisors (1).

21223201541 is an equidigital number, since it uses as much as digits as its factorization.

21223201541 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 960, while the sum is 23.

Adding to 21223201541 its reverse (14510232212), we get a palindrome (35733433753).

The spelling of 21223201541 in words is "twenty-one billion, two hundred twenty-three million, two hundred one thousand, five hundred forty-one".