20130221 has 8 divisors (see below), whose sum is σ = 21518784. Its totient is φ = 18784480.

The previous prime is 20130203. The next prime is 20130223. The reversal of 20130221 is 12203102.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20130221 - 2¹⁸ = 19868077 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20130223) 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 7 ways as a sum of consecutive naturals, for example, 9731 + ... + 11616.

It is an arithmetic number, because the mean of its divisors is an integer number (2689848).

Almost surely, 2^20130221 is an apocalyptic number.

It is an amenable number.

20130221 is a deficient number, since it is larger than the sum of its proper divisors (1388563).

20130221 is a wasteful number, since it uses less digits than its factorization.

20130221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21411.

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 20130221 is about 4486.6714834050. The cubic root of 20130221 is about 272.0296112875.

Adding to 20130221 its reverse (12203102), we get a palindrome (32333323).

The spelling of 20130221 in words is "twenty million, one hundred thirty thousand, two hundred twenty-one".