19699739235845 has 4 divisors (see below), whose sum is σ = 23639687083020. Its totient is φ = 15759791388672.

The previous prime is 19699739235833. The next prime is 19699739235877. The reversal of 19699739235845 is 54853293799691.

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 5643845959684 + 14055893276161 = 2375678^2 + 3749119^2 .

It is a cyclic number.

It is not a de Polignac number, because 19699739235845 - 2⁴ = 19699739235829 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19699739235845.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1969973923580 + ... + 1969973923589.

It is an arithmetic number, because the mean of its divisors is an integer number (5909921770755).

Almost surely, 2^{19699739235845} is an apocalyptic number.

It is an amenable number.

19699739235845 is a deficient number, since it is larger than the sum of its proper divisors (3939947847175).

19699739235845 is an equidigital number, since it uses as much as digits as its factorization.

19699739235845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3939947847174.

The product of its digits is 3968092800, while the sum is 80.

The spelling of 19699739235845 in words is "nineteen trillion, six hundred ninety-nine billion, seven hundred thirty-nine million, two hundred thirty-five thousand, eight hundred forty-five".