20531232 has 90 divisors (see below), whose sum is σ = 61067853. Its totient is φ = 6766848.

The previous prime is 20531219. The next prime is 20531243. The reversal of 20531232 is 23213502.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 2 ways, for example, as 18352656 + 2178576 = 4284^2 + 1476^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=3204.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 230644 + ... + 230732.

Almost surely, 2^20531232 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 20531232

20531232 is an abundant number, since it is smaller than the sum of its proper divisors (40536621).

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

20531232 is an frugal number, since it uses more digits than its factorization.

20531232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200 (or 94 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 18.

The square root of 20531232 is about 4531.1402538434. The cubic root of 20531232 is about 273.8241007882.

Multiplying 20531232 by its sum of digits (18), we get a square (369562176 = 19224²).

20531232 divided by its sum of digits (18) gives a square (1140624 = 1068²).

Adding to 20531232 its reverse (23213502), we get a palindrome (43744734).

The spelling of 20531232 in words is "twenty million, five hundred thirty-one thousand, two hundred thirty-two".