20113530 has 64 divisors (see below), whose sum is σ = 50889600. Its totient is φ = 5080320.

The previous prime is 20113507. The next prime is 20113537. The reversal of 20113530 is 3531102.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is not an unprimeable number, because it can be changed into a prime (20113537) 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 31 ways as a sum of consecutive naturals, for example, 52881 + ... + 53259.

It is an arithmetic number, because the mean of its divisors is an integer number (795150).

Almost surely, 2^20113530 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20113530, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25444800).

20113530 is an abundant number, since it is smaller than the sum of its proper divisors (30776070).

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

20113530 is a wasteful number, since it uses less digits than its factorization.

20113530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 479.

The product of its (nonzero) digits is 90, while the sum is 15.

The square root of 20113530 is about 4484.8110328084. The cubic root of 20113530 is about 271.9544059246.

Adding to 20113530 its reverse (3531102), we get a palindrome (23644632).

It can be divided in two parts, 201 and 13530, that added together give a palindrome (13731).

The spelling of 20113530 in words is "twenty million, one hundred thirteen thousand, five hundred thirty".