81684708143 has 2 divisors, whose sum is σ = 81684708144. Its totient is φ = 81684708142.

The previous prime is 81684708037. The next prime is 81684708179. The reversal of 81684708143 is 34180748618.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81684708143 - 2¹⁶ = 81684642607 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81684708091 and 81684708100.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81684708643) 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 as a sum of consecutive naturals, namely, 40842354071 + 40842354072.

It is an arithmetic number, because the mean of its divisors is an integer number (40842354072).

Almost surely, 2^81684708143 is an apocalyptic number.

81684708143 is a deficient number, since it is larger than the sum of its proper divisors (1).

81684708143 is an equidigital number, since it uses as much as digits as its factorization.

81684708143 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1032192, while the sum is 50.

The spelling of 81684708143 in words is "eighty-one billion, six hundred eighty-four million, seven hundred eight thousand, one hundred forty-three".