20384261 has 2 divisors, whose sum is σ = 20384262. Its totient is φ = 20384260.

The previous prime is 20384251. The next prime is 20384263. The reversal of 20384261 is 16248302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17724100 + 2660161 = 4210^2 + 1631^2 .

It is a cyclic number.

It is not a de Polignac number, because 20384261 - 2⁶ = 20384197 is a prime.

It is a super-2 number, since 2×20384261² = 831036193032242, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 20384263, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20384261.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20384263) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10192130 + 10192131.

It is an arithmetic number, because the mean of its divisors is an integer number (10192131).

Almost surely, 2^20384261 is an apocalyptic number.

It is an amenable number.

20384261 is a deficient number, since it is larger than the sum of its proper divisors (1).

20384261 is an equidigital number, since it uses as much as digits as its factorization.

20384261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 20384261 is about 4514.8932434776. The cubic root of 20384261 is about 273.1691536679.

The spelling of 20384261 in words is "twenty million, three hundred eighty-four thousand, two hundred sixty-one".