221308 has 12 divisors (see below), whose sum is σ = 394072. Its totient is φ = 108720.

The previous prime is 221303. The next prime is 221311. The reversal of 221308 is 803122.

It is a happy number.

221308 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a plaindrome in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 221291 and 221300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221303) by changing a digit.

221308 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 210 + ... + 697.

2²²¹³⁰⁸ is an apocalyptic number.

It is an amenable number.

221308 is a deficient number, since it is larger than the sum of its proper divisors (172764).

221308 is a wasteful number, since it uses less digits than its factorization.

221308 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 972 (or 970 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 221308 is about 470.4338423200. The cubic root of 221308 is about 60.4875096588.

It can be divided in two parts, 221 and 308, that added together give a square (529 = 23²).

The spelling of 221308 in words is "two hundred twenty-one thousand, three hundred eight".