20005500 has 48 divisors (see below), whose sum is σ = 58260384. Its totient is φ = 5334400.

The previous prime is 20005483. The next prime is 20005501. The reversal of 20005500 is 550002.

It is a Harshad number since it is a multiple of its sum of digits (12).

20005500 is a modest number, since divided by 5500 gives 2000 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20005501) 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 15 ways as a sum of consecutive naturals, for example, 5169 + ... + 8168.

It is an arithmetic number, because the mean of its divisors is an integer number (1213758).

Almost surely, 2^20005500 is an apocalyptic number.

20005500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20005500 is an abundant number, since it is smaller than the sum of its proper divisors (38254884).

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

20005500 is a wasteful number, since it uses less digits than its factorization.

20005500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13359 (or 13347 counting only the distinct ones).

The product of its (nonzero) digits is 50, while the sum is 12.

The square root of 20005500 is about 4472.7508314235. The cubic root of 20005500 is about 271.4666415405.

Adding to 20005500 its reverse (550002), we get a palindrome (20555502).

The spelling of 20005500 in words is "twenty million, five thousand, five hundred".