221528799 has 12 divisors (see below), whose sum is σ = 320220576. Its totient is φ = 147577632.

The previous prime is 221528777. The next prime is 221528831. The reversal of 221528799 is 997825122.

It is a happy number.

It is not a de Polignac number, because 221528799 - 2¹⁵ = 221496031 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221520799) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5107 + ... + 21659.

It is an arithmetic number, because the mean of its divisors is an integer number (26685048).

Almost surely, 2^221528799 is an apocalyptic number.

221528799 is a deficient number, since it is larger than the sum of its proper divisors (98691777).

221528799 is a wasteful number, since it uses less digits than its factorization.

221528799 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18046 (or 18043 counting only the distinct ones).

The product of its digits is 181440, while the sum is 45.

The square root of 221528799 is about 14883.8435560174. The cubic root of 221528799 is about 605.0761910283.

The spelling of 221528799 in words is "two hundred twenty-one million, five hundred twenty-eight thousand, seven hundred ninety-nine".