221730408 has 48 divisors (see below), whose sum is σ = 605856420. Its totient is φ = 73253376.

The previous prime is 221730391. The next prime is 221730463. The reversal of 221730408 is 804037122.

221730408 is a `hidden beast` number, since 221 + 7 + 30 + 408 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 199996164 + 21734244 = 14142^2 + 4662^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5491 + ... + 21762.

Almost surely, 2^221730408 is an apocalyptic number.

It is an amenable number.

221730408 is an abundant number, since it is smaller than the sum of its proper divisors (384126012).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221730408 is a wasteful number, since it uses less digits than its factorization.

221730408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27378 (or 27371 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 221730408 is about 14890.6147623260. The cubic root of 221730408 is about 605.2596913504.

The spelling of 221730408 in words is "two hundred twenty-one million, seven hundred thirty thousand, four hundred eight".