19888243 has 2 divisors, whose sum is σ = 19888244. Its totient is φ = 19888242.

The previous prime is 19888237. The next prime is 19888247. The reversal of 19888243 is 34288891.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19888243 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19888243.

It is not a weakly prime, because it can be changed into another prime (19888247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9944121 + 9944122.

It is an arithmetic number, because the mean of its divisors is an integer number (9944122).

Almost surely, 2^19888243 is an apocalyptic number.

19888243 is a deficient number, since it is larger than the sum of its proper divisors (1).

19888243 is an equidigital number, since it uses as much as digits as its factorization.

19888243 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 110592, while the sum is 43.

The square root of 19888243 is about 4459.6236388287. The cubic root of 19888243 is about 270.9352250518.

The spelling of 19888243 in words is "nineteen million, eight hundred eighty-eight thousand, two hundred forty-three".