20042550 has 72 divisors (see below), whose sum is σ = 58757400. Its totient is φ = 4857600.

The previous prime is 20042527. The next prime is 20042551. The reversal of 20042550 is 5524002.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20042551) 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 35 ways as a sum of consecutive naturals, for example, 2926 + ... + 6974.

It is an arithmetic number, because the mean of its divisors is an integer number (816075).

Almost surely, 2^20042550 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20042550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29378700).

20042550 is an abundant number, since it is smaller than the sum of its proper divisors (38714850).

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

20042550 is a wasteful number, since it uses less digits than its factorization.

20042550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4078 (or 4070 counting only the distinct ones).

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

The square root of 20042550 is about 4476.8906620555. The cubic root of 20042550 is about 271.6341227571.

Adding to 20042550 its reverse (5524002), we get a palindrome (25566552).

It can be divided in two parts, 2004 and 2550, that added together give a palindrome (4554).

The spelling of 20042550 in words is "twenty million, forty-two thousand, five hundred fifty".