1688942939 has 2 divisors, whose sum is σ = 1688942940. Its totient is φ = 1688942938.

The previous prime is 1688942921. The next prime is 1688942947. The reversal of 1688942939 is 9392498861.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1688942939 - 2¹⁶ = 1688877403 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (1688942989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 844471469 + 844471470.

It is an arithmetic number, because the mean of its divisors is an integer number (844471470).

Almost surely, 2^1688942939 is an apocalyptic number.

1688942939 is a deficient number, since it is larger than the sum of its proper divisors (1).

1688942939 is an equidigital number, since it uses as much as digits as its factorization.

1688942939 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6718464, while the sum is 59.

The square root of 1688942939 is about 41096.7509543029. The cubic root of 1688942939 is about 1190.8900290266.

The spelling of 1688942939 in words is "one billion, six hundred eighty-eight million, nine hundred forty-two thousand, nine hundred thirty-nine".