1694784820109 has 4 divisors (see below), whose sum is σ = 1694795144316. Its totient is φ = 1694774495904.

The previous prime is 1694784820073. The next prime is 1694784820111. The reversal of 1694784820109 is 9010284874961.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 810714757609 + 884070062500 = 900397^2 + 940250^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1694784820109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1694784820909) 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 in 3 ways as a sum of consecutive naturals, for example, 4911824 + ... + 5245529.

It is an arithmetic number, because the mean of its divisors is an integer number (423698786079).

Almost surely, 2^{1694784820109} is an apocalyptic number.

It is an amenable number.

1694784820109 is a deficient number, since it is larger than the sum of its proper divisors (10324207).

1694784820109 is a wasteful number, since it uses less digits than its factorization.

1694784820109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10324206.

The product of its (nonzero) digits is 6967296, while the sum is 59.

The spelling of 1694784820109 in words is "one trillion, six hundred ninety-four billion, seven hundred eighty-four million, eight hundred twenty thousand, one hundred nine".