221006633 has 2 divisors, whose sum is σ = 221006634. Its totient is φ = 221006632.

The previous prime is 221006581. The next prime is 221006641. The reversal of 221006633 is 336600122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 177076249 + 43930384 = 13307^2 + 6628^2 .

It is a cyclic number.

It is not a de Polignac number, because 221006633 - 2¹⁴ = 220990249 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 221006599 and 221006608.

It is not a weakly prime, because it can be changed into another prime (221006663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110503316 + 110503317.

It is an arithmetic number, because the mean of its divisors is an integer number (110503317).

Almost surely, 2^221006633 is an apocalyptic number.

It is an amenable number.

221006633 is a deficient number, since it is larger than the sum of its proper divisors (1).

221006633 is an equidigital number, since it uses as much as digits as its factorization.

221006633 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 23.

The square root of 221006633 is about 14866.2918375767. The cubic root of 221006633 is about 604.6004082201.

Adding to 221006633 its reverse (336600122), we get a palindrome (557606755).

The spelling of 221006633 in words is "two hundred twenty-one million, six thousand, six hundred thirty-three".