194644380709 has 2 divisors, whose sum is σ = 194644380710. Its totient is φ = 194644380708.

The previous prime is 194644380683. The next prime is 194644380731. The reversal of 194644380709 is 907083446491.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 167810664609 + 26833716100 = 409647^2 + 163810^2 .

It is a cyclic number.

It is not a de Polignac number, because 194644380709 - 2¹⁵ = 194644347941 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 194644380709.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (194644380109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97322190354 + 97322190355.

It is an arithmetic number, because the mean of its divisors is an integer number (97322190355).

Almost surely, 2^194644380709 is an apocalyptic number.

It is an amenable number.

194644380709 is a deficient number, since it is larger than the sum of its proper divisors (1).

194644380709 is an equidigital number, since it uses as much as digits as its factorization.

194644380709 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5225472, while the sum is 55.

The spelling of 194644380709 in words is "one hundred ninety-four billion, six hundred forty-four million, three hundred eighty thousand, seven hundred nine".