16661224 has 16 divisors (see below), whose sum is σ = 33077700. Its totient is φ = 7840512.

The previous prime is 16661221. The next prime is 16661237. The reversal of 16661224 is 42216661.

It can be written as a sum of positive squares in 2 ways, for example, as 12376324 + 4284900 = 3518^2 + 2070^2 .

It is a junction number, because it is equal to n+sod(n) for n = 16661192 and 16661201.

It is not an unprimeable number, because it can be changed into a prime (16661221) 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, 61119 + ... + 61390.

Almost surely, 2^16661224 is an apocalyptic number.

It is an amenable number.

16661224 is a deficient number, since it is larger than the sum of its proper divisors (16416476).

16661224 is a wasteful number, since it uses less digits than its factorization.

16661224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122532 (or 122528 counting only the distinct ones).

The product of its digits is 3456, while the sum is 28.

The square root of 16661224 is about 4081.8162624008. The cubic root of 16661224 is about 255.4086693253.

Adding to 16661224 its reverse (42216661), we get a palindrome (58877885).

It can be divided in two parts, 1666 and 1224, that multiplied together give a square (2039184 = 1428²).

The spelling of 16661224 in words is "sixteen million, six hundred sixty-one thousand, two hundred twenty-four".