1681844543 has 8 divisors (see below), whose sum is σ = 1686288912. Its totient is φ = 1677407616.

The previous prime is 1681844513. The next prime is 1681844551. The reversal of 1681844543 is 3454481861.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1681844543 - 2¹⁶ = 1681779007 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1681844494 and 1681844503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1681844513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1032896 + ... + 1034522.

It is an arithmetic number, because the mean of its divisors is an integer number (210786114).

Almost surely, 2^1681844543 is an apocalyptic number.

1681844543 is a deficient number, since it is larger than the sum of its proper divisors (4444369).

1681844543 is a wasteful number, since it uses less digits than its factorization.

1681844543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3721.

The product of its digits is 368640, while the sum is 44.

The square root of 1681844543 is about 41010.2980115970. The cubic root of 1681844543 is about 1189.2193036292.

The spelling of 1681844543 in words is "one billion, six hundred eighty-one million, eight hundred forty-four thousand, five hundred forty-three".