21126067289 has 2 divisors, whose sum is σ = 21126067290. Its totient is φ = 21126067288.

The previous prime is 21126067241. The next prime is 21126067321. The reversal of 21126067289 is 98276062112.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18834817600 + 2291249689 = 137240^2 + 47867^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21126067289 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 (21126067219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10563033644 + 10563033645.

It is an arithmetic number, because the mean of its divisors is an integer number (10563033645).

Almost surely, 2^21126067289 is an apocalyptic number.

It is an amenable number.

21126067289 is a deficient number, since it is larger than the sum of its proper divisors (1).

21126067289 is an equidigital number, since it uses as much as digits as its factorization.

21126067289 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 145152, while the sum is 44.

The spelling of 21126067289 in words is "twenty-one billion, one hundred twenty-six million, sixty-seven thousand, two hundred eighty-nine".