19897079 has 2 divisors, whose sum is σ = 19897080. Its totient is φ = 19897078.

The previous prime is 19897067. The next prime is 19897109. The reversal of 19897079 is 97079891.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19897079 - 2⁴ = 19897063 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19897049) 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, 9948539 + 9948540.

It is an arithmetic number, because the mean of its divisors is an integer number (9948540).

Almost surely, 2^19897079 is an apocalyptic number.

19897079 is a deficient number, since it is larger than the sum of its proper divisors (1).

19897079 is an equidigital number, since it uses as much as digits as its factorization.

19897079 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 285768, while the sum is 50.

The square root of 19897079 is about 4460.6141953771. The cubic root of 19897079 is about 270.9753430452.

The spelling of 19897079 in words is "nineteen million, eight hundred ninety-seven thousand, seventy-nine".