19678249 has 2 divisors, whose sum is σ = 19678250. Its totient is φ = 19678248.

The previous prime is 19678247. The next prime is 19678283. The reversal of 19678249 is 94287691.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18766224 + 912025 = 4332^2 + 955^2 .

It is a cyclic number.

It is not a de Polignac number, because 19678249 - 2¹ = 19678247 is a prime.

Together with 19678247, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 19678199 and 19678208.

It is not a weakly prime, because it can be changed into another prime (19678247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9839124 + 9839125.

It is an arithmetic number, because the mean of its divisors is an integer number (9839125).

Almost surely, 2^19678249 is an apocalyptic number.

It is an amenable number.

19678249 is a deficient number, since it is larger than the sum of its proper divisors (1).

19678249 is an equidigital number, since it uses as much as digits as its factorization.

19678249 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 217728, while the sum is 46.

The square root of 19678249 is about 4436.0172452325. The cubic root of 19678249 is about 269.9782744293.

The spelling of 19678249 in words is "nineteen million, six hundred seventy-eight thousand, two hundred forty-nine".