19428109 has 2 divisors, whose sum is σ = 19428110. Its totient is φ = 19428108.

The previous prime is 19428091. The next prime is 19428121. The reversal of 19428109 is 90182491.

Together with previous prime (19428091) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9954025 + 9474084 = 3155^2 + 3078^2 .

It is a cyclic number.

It is not a de Polignac number, because 19428109 - 2¹¹ = 19426061 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19428179) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9714054 + 9714055.

It is an arithmetic number, because the mean of its divisors is an integer number (9714055).

Almost surely, 2^19428109 is an apocalyptic number.

It is an amenable number.

19428109 is a deficient number, since it is larger than the sum of its proper divisors (1).

19428109 is an equidigital number, since it uses as much as digits as its factorization.

19428109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 34.

The square root of 19428109 is about 4407.7328639563. The cubic root of 19428109 is about 268.8294501714.

The spelling of 19428109 in words is "nineteen million, four hundred twenty-eight thousand, one hundred nine".