81983778683 has 2 divisors, whose sum is σ = 81983778684. Its totient is φ = 81983778682.

The previous prime is 81983778659. The next prime is 81983778727. The reversal of 81983778683 is 38687738918.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81983778683 - 2⁸ = 81983778427 is a prime.

It is not a weakly prime, because it can be changed into another prime (81983778983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40991889341 + 40991889342.

It is an arithmetic number, because the mean of its divisors is an integer number (40991889342).

Almost surely, 2^81983778683 is an apocalyptic number.

81983778683 is a deficient number, since it is larger than the sum of its proper divisors (1).

81983778683 is an equidigital number, since it uses as much as digits as its factorization.

81983778683 is an evil number, because the sum of its binary digits is even.

The product of its digits is 97542144, while the sum is 68.

The spelling of 81983778683 in words is "eighty-one billion, nine hundred eighty-three million, seven hundred seventy-eight thousand, six hundred eighty-three".