1680626993 has 2 divisors, whose sum is σ = 1680626994. Its totient is φ = 1680626992.

The previous prime is 1680626939. The next prime is 1680627019. The reversal of 1680626993 is 3996260861.

Together with previous prime (1680626939) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 977687824 + 702939169 = 31268^2 + 26513^2 .

It is a cyclic number.

It is not a de Polignac number, because 1680626993 - 2⁶ = 1680626929 is a prime.

It is not a weakly prime, because it can be changed into another prime (1680626923) 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, 840313496 + 840313497.

It is an arithmetic number, because the mean of its divisors is an integer number (840313497).

Almost surely, 2^1680626993 is an apocalyptic number.

It is an amenable number.

1680626993 is a deficient number, since it is larger than the sum of its proper divisors (1).

1680626993 is an equidigital number, since it uses as much as digits as its factorization.

1680626993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 839808, while the sum is 50.

The square root of 1680626993 is about 40995.4508817747. The cubic root of 1680626993 is about 1188.9322609465.

The spelling of 1680626993 in words is "one billion, six hundred eighty million, six hundred twenty-six thousand, nine hundred ninety-three".