20530320 has 80 divisors (see below), whose sum is σ = 64228032. Its totient is φ = 5424640.

The previous prime is 20530313. The next prime is 20530327. The reversal of 20530320 is 2303502.

It is an interprime number because it is at equal distance from previous prime (20530313) and next prime (20530327).

It is a tau number, because it is divible by the number of its divisors (80).

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

It is a self number, because there is not a number n which added to its sum of digits gives 20530320.

It is not an unprimeable number, because it can be changed into a prime (20530327) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31114 + ... + 31766.

Almost surely, 2^20530320 is an apocalyptic number.

20530320 is a gapful number since it is divisible by the number (20) 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 20530320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32114016).

20530320 is an abundant number, since it is smaller than the sum of its proper divisors (43697712).

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

20530320 is a wasteful number, since it uses less digits than its factorization.

20530320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 800 (or 794 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 15.

The square root of 20530320 is about 4531.0396158056. The cubic root of 20530320 is about 273.8200462941.

Adding to 20530320 its reverse (2303502), we get a palindrome (22833822).

The spelling of 20530320 in words is "twenty million, five hundred thirty thousand, three hundred twenty".