1681986679 has 2 divisors, whose sum is σ = 1681986680. Its totient is φ = 1681986678.

The previous prime is 1681986673. The next prime is 1681986707. The reversal of 1681986679 is 9766891861.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1681986679 - 2¹⁷ = 1681855607 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1681986673) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 840993339 + 840993340.

It is an arithmetic number, because the mean of its divisors is an integer number (840993340).

Almost surely, 2^1681986679 is an apocalyptic number.

1681986679 is a deficient number, since it is larger than the sum of its proper divisors (1).

1681986679 is an equidigital number, since it uses as much as digits as its factorization.

1681986679 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7838208, while the sum is 61.

The square root of 1681986679 is about 41012.0309055770. The cubic root of 1681986679 is about 1189.2528037752.

The spelling of 1681986679 in words is "one billion, six hundred eighty-one million, nine hundred eighty-six thousand, six hundred seventy-nine".