20889859 has 2 divisors, whose sum is σ = 20889860. Its totient is φ = 20889858.

The previous prime is 20889857. The next prime is 20889871. The reversal of 20889859 is 95898802.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20889859 - 2¹ = 20889857 is a prime.

Together with 20889857, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (20889857) 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, 10444929 + 10444930.

It is an arithmetic number, because the mean of its divisors is an integer number (10444930).

Almost surely, 2^20889859 is an apocalyptic number.

20889859 is a deficient number, since it is larger than the sum of its proper divisors (1).

20889859 is an equidigital number, since it uses as much as digits as its factorization.

20889859 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 414720, while the sum is 49.

The square root of 20889859 is about 4570.5425279719. The cubic root of 20889859 is about 275.4092375286.

The spelling of 20889859 in words is "twenty million, eight hundred eighty-nine thousand, eight hundred fifty-nine".