19684139 has 2 divisors, whose sum is σ = 19684140. Its totient is φ = 19684138.

The previous prime is 19684129. The next prime is 19684177. The reversal of 19684139 is 93148691.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19684139 - 2¹² = 19680043 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 19684096 and 19684105.

It is not a weakly prime, because it can be changed into another prime (19684129) 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, 9842069 + 9842070.

It is an arithmetic number, because the mean of its divisors is an integer number (9842070).

Almost surely, 2^19684139 is an apocalyptic number.

19684139 is a deficient number, since it is larger than the sum of its proper divisors (1).

19684139 is an equidigital number, since it uses as much as digits as its factorization.

19684139 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46656, while the sum is 41.

The square root of 19684139 is about 4436.6810793655. The cubic root of 19684139 is about 270.0052079471.

The spelling of 19684139 in words is "nineteen million, six hundred eighty-four thousand, one hundred thirty-nine".