20306289 has 8 divisors (see below), whose sum is σ = 27114112. Its totient is φ = 13518000.

The previous prime is 20306257. The next prime is 20306291. The reversal of 20306289 is 98260302.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20306289 - 2⁵ = 20306257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20306389) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2254 + ... + 6759.

It is an arithmetic number, because the mean of its divisors is an integer number (3389264).

Almost surely, 2^20306289 is an apocalyptic number.

It is an amenable number.

20306289 is a deficient number, since it is larger than the sum of its proper divisors (6807823).

20306289 is an equidigital number, since it uses as much as digits as its factorization.

20306289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9767.

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 20306289 is about 4506.2499930652. The cubic root of 20306289 is about 272.8204081203.

The spelling of 20306289 in words is "twenty million, three hundred six thousand, two hundred eighty-nine".