20316389 has 2 divisors, whose sum is σ = 20316390. Its totient is φ = 20316388.

The previous prime is 20316347. The next prime is 20316391. The reversal of 20316389 is 98361302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15864289 + 4452100 = 3983^2 + 2110^2 .

It is a cyclic number.

It is not a de Polignac number, because 20316389 - 2⁸ = 20316133 is a prime.

Together with 20316391, 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 (20316319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10158194 + 10158195.

It is an arithmetic number, because the mean of its divisors is an integer number (10158195).

Almost surely, 2^20316389 is an apocalyptic number.

It is an amenable number.

20316389 is a deficient number, since it is larger than the sum of its proper divisors (1).

20316389 is an equidigital number, since it uses as much as digits as its factorization.

20316389 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 20316389 is about 4507.3705194936. The cubic root of 20316389 is about 272.8656326876.

The spelling of 20316389 in words is "twenty million, three hundred sixteen thousand, three hundred eighty-nine".