20385121 has 2 divisors, whose sum is σ = 20385122. Its totient is φ = 20385120.

The previous prime is 20385083. The next prime is 20385143. The reversal of 20385121 is 12158302.

It is an a-pointer prime, because the next prime (20385143) can be obtained adding 20385121 to its sum of digits (22).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20070400 + 314721 = 4480^2 + 561^2 .

It is a cyclic number.

It is not a de Polignac number, because 20385121 - 2¹⁷ = 20254049 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20385092 and 20385101.

It is not a weakly prime, because it can be changed into another prime (20385181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10192560 + 10192561.

It is an arithmetic number, because the mean of its divisors is an integer number (10192561).

Almost surely, 2^20385121 is an apocalyptic number.

It is an amenable number.

20385121 is a deficient number, since it is larger than the sum of its proper divisors (1).

20385121 is an equidigital number, since it uses as much as digits as its factorization.

20385121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 20385121 is about 4514.9884828203. The cubic root of 20385121 is about 273.1729952293.

The spelling of 20385121 in words is "twenty million, three hundred eighty-five thousand, one hundred twenty-one".