20735172 has 54 divisors (see below), whose sum is σ = 55706378. Its totient is φ = 6501888.

The previous prime is 20735153. The next prime is 20735173. The reversal of 20735172 is 27153702.

It can be written as a sum of positive squares in 3 ways, for example, as 10850436 + 9884736 = 3294^2 + 3144^2 .

It is not an unprimeable number, because it can be changed into a prime (20735173) 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 17 ways as a sum of consecutive naturals, for example, 9408 + ... + 11400.

Almost surely, 2^20735172 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20735172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27853189).

20735172 is an abundant number, since it is smaller than the sum of its proper divisors (34971206).

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

20735172 is a wasteful number, since it uses less digits than its factorization.

20735172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2037 (or 2015 counting only the distinct ones).

The product of its (nonzero) digits is 2940, while the sum is 27.

The square root of 20735172 is about 4553.5889142521. The cubic root of 20735172 is about 274.7277614381.

Adding to 20735172 its reverse (27153702), we get a palindrome (47888874).

The spelling of 20735172 in words is "twenty million, seven hundred thirty-five thousand, one hundred seventy-two".