20128679 has 2 divisors, whose sum is σ = 20128680. Its totient is φ = 20128678.

The previous prime is 20128631. The next prime is 20128681. The reversal of 20128679 is 97682102.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20128679 is a prime.

Together with 20128681, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20128699) 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, 10064339 + 10064340.

It is an arithmetic number, because the mean of its divisors is an integer number (10064340).

Almost surely, 2^20128679 is an apocalyptic number.

20128679 is a deficient number, since it is larger than the sum of its proper divisors (1).

20128679 is an equidigital number, since it uses as much as digits as its factorization.

20128679 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 20128679 is about 4486.4996378023. The cubic root of 20128679 is about 272.0226651745.

The spelling of 20128679 in words is "twenty million, one hundred twenty-eight thousand, six hundred seventy-nine".