20389547 has 2 divisors, whose sum is σ = 20389548. Its totient is φ = 20389546.

The previous prime is 20389543. The next prime is 20389549. The reversal of 20389547 is 74598302.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20389547 - 2² = 20389543 is a prime.

Together with 20389549, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20389547.

It is not a weakly prime, because it can be changed into another prime (20389541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10194773 + 10194774.

It is an arithmetic number, because the mean of its divisors is an integer number (10194774).

Almost surely, 2^20389547 is an apocalyptic number.

20389547 is a deficient number, since it is larger than the sum of its proper divisors (1).

20389547 is an equidigital number, since it uses as much as digits as its factorization.

20389547 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 60480, while the sum is 38.

The square root of 20389547 is about 4515.4786014331. The cubic root of 20389547 is about 273.1927641608.

The spelling of 20389547 in words is "twenty million, three hundred eighty-nine thousand, five hundred forty-seven".