20842279 has 2 divisors, whose sum is σ = 20842280. Its totient is φ = 20842278.

The previous prime is 20842277. The next prime is 20842319. The reversal of 20842279 is 97224802.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20842279 - 2¹ = 20842277 is a prime.

Together with 20842277, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20842277) 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, 10421139 + 10421140.

It is an arithmetic number, because the mean of its divisors is an integer number (10421140).

Almost surely, 2^20842279 is an apocalyptic number.

20842279 is a deficient number, since it is larger than the sum of its proper divisors (1).

20842279 is an equidigital number, since it uses as much as digits as its factorization.

20842279 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16128, while the sum is 34.

The square root of 20842279 is about 4565.3344893885. The cubic root of 20842279 is about 275.1999823596.

The spelling of 20842279 in words is "twenty million, eight hundred forty-two thousand, two hundred seventy-nine".