20205020 has 24 divisors (see below), whose sum is σ = 46288368. Its totient is φ = 7347200.

The previous prime is 20205001. The next prime is 20205023. The reversal of 20205020 is 2050202.

It is a Harshad number since it is a multiple of its sum of digits (11).

It is a junction number, because it is equal to n+sod(n) for n = 20204992 and 20205010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20205023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45701 + ... + 46140.

It is an arithmetic number, because the mean of its divisors is an integer number (1928682).

Almost surely, 2^20205020 is an apocalyptic number.

20205020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20205020 is an abundant number, since it is smaller than the sum of its proper divisors (26083348).

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

20205020 is a wasteful number, since it uses less digits than its factorization.

20205020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91861 (or 91859 counting only the distinct ones).

The product of its (nonzero) digits is 40, while the sum is 11.

The square root of 20205020 is about 4494.9994438264. Note that the first 3 decimals coincide. The cubic root of 20205020 is about 272.3661267621.

Adding to 20205020 its reverse (2050202), we get a palindrome (22255222).

The spelling of 20205020 in words is "twenty million, two hundred five thousand, twenty".