221530245 has 8 divisors (see below), whose sum is σ = 354448416. Its totient is φ = 118149456.

The previous prime is 221530229. The next prime is 221530271. The reversal of 221530245 is 542035122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 221530245 - 2⁴ = 221530229 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7384327 + ... + 7384356.

It is an arithmetic number, because the mean of its divisors is an integer number (44306052).

Almost surely, 2^221530245 is an apocalyptic number.

It is an amenable number.

221530245 is a deficient number, since it is larger than the sum of its proper divisors (132918171).

221530245 is a wasteful number, since it uses less digits than its factorization.

221530245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14768691.

The product of its (nonzero) digits is 2400, while the sum is 24.

The square root of 221530245 is about 14883.8921321004. The cubic root of 221530245 is about 605.0775075437.

Adding to 221530245 its reverse (542035122), we get a palindrome (763565367).

The spelling of 221530245 in words is "two hundred twenty-one million, five hundred thirty thousand, two hundred forty-five".