21445810289 has 2 divisors, whose sum is σ = 21445810290. Its totient is φ = 21445810288.

The previous prime is 21445810249. The next prime is 21445810303. The reversal of 21445810289 is 98201854412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13370990689 + 8074819600 = 115633^2 + 89860^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21445810289 is a prime.

It is not a weakly prime, because it can be changed into another prime (21445810229) 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, 10722905144 + 10722905145.

It is an arithmetic number, because the mean of its divisors is an integer number (10722905145).

Almost surely, 2^21445810289 is an apocalyptic number.

It is an amenable number.

21445810289 is a deficient number, since it is larger than the sum of its proper divisors (1).

21445810289 is an equidigital number, since it uses as much as digits as its factorization.

21445810289 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 184320, while the sum is 44.

The spelling of 21445810289 in words is "twenty-one billion, four hundred forty-five million, eight hundred ten thousand, two hundred eighty-nine".