1681823543 has 2 divisors, whose sum is σ = 1681823544. Its totient is φ = 1681823542.

The previous prime is 1681823483. The next prime is 1681823573. The reversal of 1681823543 is 3453281861.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1681823543 - 2²⁸ = 1413388087 is a prime.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1681823543.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1681823573) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 840911771 + 840911772.

It is an arithmetic number, because the mean of its divisors is an integer number (840911772).

Almost surely, 2^1681823543 is an apocalyptic number.

1681823543 is a deficient number, since it is larger than the sum of its proper divisors (1).

1681823543 is an equidigital number, since it uses as much as digits as its factorization.

1681823543 is an evil number, because the sum of its binary digits is even.

The product of its digits is 138240, while the sum is 41.

The square root of 1681823543 is about 41010.0419775450. The cubic root of 1681823543 is about 1189.2143539626.

The spelling of 1681823543 in words is "one billion, six hundred eighty-one million, eight hundred twenty-three thousand, five hundred forty-three".