19981223 has 2 divisors, whose sum is σ = 19981224. Its totient is φ = 19981222.

The previous prime is 19981207. The next prime is 19981229. The reversal of 19981223 is 32218991.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 19981223 - 2⁴ = 19981207 is a prime.

It is equal to p_1269485 and since 19981223 and 1269485 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19981229) 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, 9990611 + 9990612.

It is an arithmetic number, because the mean of its divisors is an integer number (9990612).

Almost surely, 2^19981223 is an apocalyptic number.

19981223 is a deficient number, since it is larger than the sum of its proper divisors (1).

19981223 is an equidigital number, since it uses as much as digits as its factorization.

19981223 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7776, while the sum is 35.

The square root of 19981223 is about 4470.0361296079. The cubic root of 19981223 is about 271.3567873619.

The spelling of 19981223 in words is "nineteen million, nine hundred eighty-one thousand, two hundred twenty-three".