20535320 has 128 divisors (see below), whose sum is σ = 55520640. Its totient is φ = 6758400.

The previous prime is 20535293. The next prime is 20535323. The reversal of 20535320 is 2353502.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 20535292 and 20535301.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20535323) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 203270 + ... + 203370.

It is an arithmetic number, because the mean of its divisors is an integer number (433755).

Almost surely, 2^20535320 is an apocalyptic number.

20535320 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 20535320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27760320).

20535320 is an abundant number, since it is smaller than the sum of its proper divisors (34985320).

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

20535320 is a wasteful number, since it uses less digits than its factorization.

20535320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165 (or 161 counting only the distinct ones).

The product of its (nonzero) digits is 900, while the sum is 20.

The square root of 20535320 is about 4531.5913319716. The cubic root of 20535320 is about 273.8422734050.

Adding to 20535320 its reverse (2353502), we get a palindrome (22888822).

The spelling of 20535320 in words is "twenty million, five hundred thirty-five thousand, three hundred twenty".