20505222 has 24 divisors (see below), whose sum is σ = 44871840. Its totient is φ = 6766800.

The previous prime is 20505217. The next prime is 20505227. The reversal of 20505222 is 22250502.

It is an interprime number because it is at equal distance from previous prime (20505217) and next prime (20505227).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 20505195 and 20505204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20505227) 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 11 ways as a sum of consecutive naturals, for example, 3822 + ... + 7457.

It is an arithmetic number, because the mean of its divisors is an integer number (1869660).

Almost surely, 2^20505222 is an apocalyptic number.

20505222 is an abundant number, since it is smaller than the sum of its proper divisors (24366618).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20505222 is a wasteful number, since it uses less digits than its factorization.

20505222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11388 (or 11385 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 18.

The square root of 20505222 is about 4528.2692057783. The cubic root of 20505222 is about 273.7084205317.

Adding to 20505222 its reverse (22250502), we get a palindrome (42755724).

The spelling of 20505222 in words is "twenty million, five hundred five thousand, two hundred twenty-two".