20145504 has 48 divisors (see below), whose sum is σ = 53231472. Its totient is φ = 6670848.

The previous prime is 20145487. The next prime is 20145509. The reversal of 20145504 is 40554102.

It is a tau number, because it is divible by the number of its divisors (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20145509) 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 7 ways as a sum of consecutive naturals, for example, 16002 + ... + 17214.

It is an arithmetic number, because the mean of its divisors is an integer number (1108989).

Almost surely, 2^20145504 is an apocalyptic number.

20145504 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20145504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26615736).

20145504 is an abundant number, since it is smaller than the sum of its proper divisors (33085968).

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

20145504 is a wasteful number, since it uses less digits than its factorization.

20145504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1399 (or 1391 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 21.

The square root of 20145504 is about 4488.3743159411. The cubic root of 20145504 is about 272.0984361136.

Adding to 20145504 its reverse (40554102), we get a palindrome (60699606).

The spelling of 20145504 in words is "twenty million, one hundred forty-five thousand, five hundred four".