19720159 has 2 divisors, whose sum is σ = 19720160. Its totient is φ = 19720158.

The previous prime is 19720133. The next prime is 19720163. The reversal of 19720159 is 95102791.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19720159 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19720189) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9860079 + 9860080.

It is an arithmetic number, because the mean of its divisors is an integer number (9860080).

Almost surely, 2^19720159 is an apocalyptic number.

19720159 is a deficient number, since it is larger than the sum of its proper divisors (1).

19720159 is an equidigital number, since it uses as much as digits as its factorization.

19720159 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5670, while the sum is 34.

The square root of 19720159 is about 4440.7385646984. The cubic root of 19720159 is about 270.1698017406.

The spelling of 19720159 in words is "nineteen million, seven hundred twenty thousand, one hundred fifty-nine".