21965103709 has 2 divisors, whose sum is σ = 21965103710. Its totient is φ = 21965103708.

The previous prime is 21965103679. The next prime is 21965103733. The reversal of 21965103709 is 90730156912.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11960703225 + 10004400484 = 109365^2 + 100022^2 .

It is a cyclic number.

It is not a de Polignac number, because 21965103709 - 2¹⁷ = 21964972637 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21965103739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10982551854 + 10982551855.

It is an arithmetic number, because the mean of its divisors is an integer number (10982551855).

Almost surely, 2^21965103709 is an apocalyptic number.

It is an amenable number.

21965103709 is a deficient number, since it is larger than the sum of its proper divisors (1).

21965103709 is an equidigital number, since it uses as much as digits as its factorization.

21965103709 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 102060, while the sum is 43.

The spelling of 21965103709 in words is "twenty-one billion, nine hundred sixty-five million, one hundred three thousand, seven hundred nine".