20233521 has 72 divisors (see below), whose sum is σ = 38342304. Its totient is φ = 10160640.

The previous prime is 20233511. The next prime is 20233523. The reversal of 20233521 is 12533202.

It is not a de Polignac number, because 20233521 - 2⁵ = 20233489 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20233494 and 20233503.

It is not an unprimeable number, because it can be changed into a prime (20233523) 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 71 ways as a sum of consecutive naturals, for example, 208545 + ... + 208641.

It is an arithmetic number, because the mean of its divisors is an integer number (532532).

Almost surely, 2^20233521 is an apocalyptic number.

20233521 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20233521 is a deficient number, since it is larger than the sum of its proper divisors (18108783).

20233521 is a wasteful number, since it uses less digits than its factorization.

20233521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171 (or 161 counting only the distinct ones).

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

The square root of 20233521 is about 4498.1686273416. The cubic root of 20233521 is about 272.4941322419.

Adding to 20233521 its reverse (12533202), we get a palindrome (32766723).

The spelling of 20233521 in words is "twenty million, two hundred thirty-three thousand, five hundred twenty-one".