20390211 has 20 divisors (see below), whose sum is σ = 32065000. Its totient is φ = 12877056.

The previous prime is 20390207. The next prime is 20390221. The reversal of 20390211 is 11209302.

It is a happy number.

It is not a de Polignac number, because 20390211 - 2² = 20390207 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20390221) 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 in 19 ways as a sum of consecutive naturals, for example, 5086 + ... + 8163.

It is an arithmetic number, because the mean of its divisors is an integer number (1603250).

Almost surely, 2^20390211 is an apocalyptic number.

20390211 is a deficient number, since it is larger than the sum of its proper divisors (11674789).

20390211 is a wasteful number, since it uses less digits than its factorization.

20390211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13280 (or 13271 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 20390211 is about 4515.5521257095. The cubic root of 20390211 is about 273.1957297004.

Adding to 20390211 its reverse (11209302), we get a palindrome (31599513).

The spelling of 20390211 in words is "twenty million, three hundred ninety thousand, two hundred eleven".