19981933 has 2 divisors, whose sum is σ = 19981934. Its totient is φ = 19981932.

The previous prime is 19981891. The next prime is 19981937. The reversal of 19981933 is 33918991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19245769 + 736164 = 4387^2 + 858^2 .

It is a cyclic number.

It is not a de Polignac number, because 19981933 - 2¹³ = 19973741 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19981933.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19981937) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9990966 + 9990967.

It is an arithmetic number, because the mean of its divisors is an integer number (9990967).

Almost surely, 2^19981933 is an apocalyptic number.

It is an amenable number.

19981933 is a deficient number, since it is larger than the sum of its proper divisors (1).

19981933 is an equidigital number, since it uses as much as digits as its factorization.

19981933 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 52488, while the sum is 43.

The square root of 19981933 is about 4470.1155466050. The cubic root of 19981933 is about 271.3600013967.

The spelling of 19981933 in words is "nineteen million, nine hundred eighty-one thousand, nine hundred thirty-three".