20240221 has 16 divisors (see below), whose sum is σ = 21625344. Its totient is φ = 18918144.

The previous prime is 20240219. The next prime is 20240257. The reversal of 20240221 is 12204202.

It is a cyclic number.

It is not a de Polignac number, because 20240221 - 2¹ = 20240219 is a prime.

It is a super-2 number, since 2×20240221² = 819333092257682, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20240261) 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, 179061 + ... + 179173.

It is an arithmetic number, because the mean of its divisors is an integer number (1351584).

Almost surely, 2^20240221 is an apocalyptic number.

It is an amenable number.

20240221 is a deficient number, since it is larger than the sum of its proper divisors (1385123).

20240221 is a wasteful number, since it uses less digits than its factorization.

20240221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 300.

The product of its (nonzero) digits is 64, while the sum is 13.

The square root of 20240221 is about 4498.9133132347. The cubic root of 20240221 is about 272.5242062497.

Adding to 20240221 its reverse (12204202), we get a palindrome (32444423).

The spelling of 20240221 in words is "twenty million, two hundred forty thousand, two hundred twenty-one".