17944429661 has 2 divisors, whose sum is σ = 17944429662. Its totient is φ = 17944429660.

The previous prime is 17944429583. The next prime is 17944429663. The reversal of 17944429661 is 16692444971.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17937512761 + 6916900 = 133931^2 + 2630^2 .

It is a cyclic number.

It is not a de Polignac number, because 17944429661 - 2¹⁰ = 17944428637 is a prime.

It is a Sophie Germain prime.

Together with 17944429663, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (17944429663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8972214830 + 8972214831.

It is an arithmetic number, because the mean of its divisors is an integer number (8972214831).

Almost surely, 2^17944429661 is an apocalyptic number.

It is an amenable number.

17944429661 is a deficient number, since it is larger than the sum of its proper divisors (1).

17944429661 is an equidigital number, since it uses as much as digits as its factorization.

17944429661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2612736, while the sum is 53.

The spelling of 17944429661 in words is "seventeen billion, nine hundred forty-four million, four hundred twenty-nine thousand, six hundred sixty-one".