19945903 has 2 divisors, whose sum is σ = 19945904. Its totient is φ = 19945902.

The previous prime is 19945901. The next prime is 19945943. The reversal of 19945903 is 30954991.

It is an a-pointer prime, because the next prime (19945943) can be obtained adding 19945903 to its sum of digits (40).

It is a weak prime.

It is an emirp because it is prime and its reverse (30954991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19945903 - 2¹ = 19945901 is a prime.

Together with 19945901, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19945901) 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, 9972951 + 9972952.

It is an arithmetic number, because the mean of its divisors is an integer number (9972952).

Almost surely, 2^19945903 is an apocalyptic number.

19945903 is a deficient number, since it is larger than the sum of its proper divisors (1).

19945903 is an equidigital number, since it uses as much as digits as its factorization.

19945903 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 43740, while the sum is 40.

The square root of 19945903 is about 4466.0836311023. The cubic root of 19945903 is about 271.1968042525.

The spelling of 19945903 in words is "nineteen million, nine hundred forty-five thousand, nine hundred three".