221307712 has 28 divisors (see below), whose sum is σ = 439951876. Its totient is φ = 110453760.

The previous prime is 221307707. The next prime is 221307719. The reversal of 221307712 is 217703122.

It can be written as a sum of positive squares in 2 ways, for example, as 105185536 + 116122176 = 10256^2 + 10776^2 .

It is a super-3 number, since 3×221307712³ (a number of 26 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221307719) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36412 + ... + 42052.

It is an arithmetic number, because the mean of its divisors is an integer number (15712567).

Almost surely, 2^221307712 is an apocalyptic number.

It is an amenable number.

221307712 is a deficient number, since it is larger than the sum of its proper divisors (218644164).

221307712 is an equidigital number, since it uses as much as digits as its factorization.

221307712 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6266 (or 6256 counting only the distinct ones).

The product of its (nonzero) digits is 1176, while the sum is 25.

The square root of 221307712 is about 14876.4146218099. The cubic root of 221307712 is about 604.8748342029.

The spelling of 221307712 in words is "two hundred twenty-one million, three hundred seven thousand, seven hundred twelve".