21122134541 has 2 divisors, whose sum is σ = 21122134542. Its totient is φ = 21122134540.

The previous prime is 21122134531. The next prime is 21122134609. The reversal of 21122134541 is 14543122112.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14357072041 + 6765062500 = 119821^2 + 82250^2 .

It is a cyclic number.

It is not a de Polignac number, because 21122134541 - 2¹⁸ = 21121872397 is a prime.

It is a super-2 number, since 2×21122134541² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21122134541.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21122134511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10561067270 + 10561067271.

It is an arithmetic number, because the mean of its divisors is an integer number (10561067271).

Almost surely, 2^21122134541 is an apocalyptic number.

It is an amenable number.

21122134541 is a deficient number, since it is larger than the sum of its proper divisors (1).

21122134541 is an equidigital number, since it uses as much as digits as its factorization.

21122134541 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1920, while the sum is 26.

Adding to 21122134541 its reverse (14543122112), we get a palindrome (35665256653).

The spelling of 21122134541 in words is "twenty-one billion, one hundred twenty-two million, one hundred thirty-four thousand, five hundred forty-one".