40221 has 12 divisors (see below), whose sum is σ = 60060. Its totient is φ = 25920.

The previous prime is 40213. The next prime is 40231. The reversal of 40221 is 12204.

40221 = 9² + 10² + ... + 49².

It can be written as a sum of positive squares in 2 ways, for example, as 12996 + 27225 = 114^2 + 165^2 .

It is not a de Polignac number, because 40221 - 2³ = 40213 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40231) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 315 + ... + 423.

It is an arithmetic number, because the mean of its divisors is an integer number (5005).

2⁴⁰²²¹ is an apocalyptic number.

40221 is a gapful number since it is divisible by the number (41) formed by its first and last digit.

It is an amenable number.

40221 is a deficient number, since it is larger than the sum of its proper divisors (19839).

40221 is a wasteful number, since it uses less digits than its factorization.

40221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156 (or 153 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

The square root of 40221 is about 200.5517389603. The cubic root of 40221 is about 34.2623874066.

Adding to 40221 its reverse (12204), we get a palindrome (52425).

The spelling of 40221 in words is "forty thousand, two hundred twenty-one", and thus it is an iban number.