221028633 has 48 divisors (see below), whose sum is σ = 379641600. Its totient is φ = 121242240.

The previous prime is 221028629. The next prime is 221028637. The reversal of 221028633 is 336820122.

221028633 is a `hidden beast` number, since 2 + 2 + 1 + 0 + 28 + 633 = 666.

It is an interprime number because it is at equal distance from previous prime (221028629) and next prime (221028637).

It is not a de Polignac number, because 221028633 - 2² = 221028629 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221028597 and 221028606.

It is not an unprimeable number, because it can be changed into a prime (221028637) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 568003 + ... + 568391.

It is an arithmetic number, because the mean of its divisors is an integer number (7909200).

Almost surely, 2^221028633 is an apocalyptic number.

It is an amenable number.

221028633 is a deficient number, since it is larger than the sum of its proper divisors (158612967).

221028633 is a wasteful number, since it uses less digits than its factorization.

221028633 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 742 (or 739 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 221028633 is about 14867.0317481332. The cubic root of 221028633 is about 604.6204691076.

Adding to 221028633 its reverse (336820122), we get a palindrome (557848755).

The spelling of 221028633 in words is "two hundred twenty-one million, twenty-eight thousand, six hundred thirty-three".