Search a number
-
+
216221 = 463467
BaseRepresentation
bin110100110010011101
3101222121012
4310302131
523404341
64345005
71560245
oct646235
9358535
10216221
111384a5
12a5165
1377555
1458b25
15440eb
hex34c9d

216221 has 4 divisors (see below), whose sum is σ = 217152. Its totient is φ = 215292.

The previous prime is 216217. The next prime is 216233. The reversal of 216221 is 122612.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 216221 - 22 = 216217 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 13.

It is a zygodrome in base 13.

It is a junction number, because it is equal to n+sod(n) for n = 216196 and 216205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 230 + ... + 696.

It is an arithmetic number, because the mean of its divisors is an integer number (54288).

2216221 is an apocalyptic number.

It is an amenable number.

216221 is a deficient number, since it is larger than the sum of its proper divisors (931).

216221 is an equidigital number, since it uses as much as digits as its factorization.

216221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 930.

The product of its digits is 48, while the sum is 14.

The square root of 216221 is about 464.9956989048. The cubic root of 216221 is about 60.0204559880.

Adding to 216221 its reverse (122612), we get a palindrome (338833).

The spelling of 216221 in words is "two hundred sixteen thousand, two hundred twenty-one".

Divisors: 1 463 467 216221