1681863136819 has 4 divisors (see below), whose sum is σ = 1693001303440. Its totient is φ = 1670724970200.

The previous prime is 1681863136817. The next prime is 1681863136823. The reversal of 1681863136819 is 9186313681861.

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

It is a cyclic number.

It is not a de Polignac number, because 1681863136819 - 2¹ = 1681863136817 is a prime.

It is a super-2 number, since 2×1681863136819² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1681863136817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5569083084 + ... + 5569083385.

It is an arithmetic number, because the mean of its divisors is an integer number (423250325860).

Almost surely, 2^{1681863136819} is an apocalyptic number.

1681863136819 is a deficient number, since it is larger than the sum of its proper divisors (11138166621).

1681863136819 is a wasteful number, since it uses less digits than its factorization.

1681863136819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11138166620.

The product of its digits is 8957952, while the sum is 61.

The spelling of 1681863136819 in words is "one trillion, six hundred eighty-one billion, eight hundred sixty-three million, one hundred thirty-six thousand, eight hundred nineteen".