221501665730 has 8 divisors (see below), whose sum is σ = 398702998332. Its totient is φ = 88600666288.

The previous prime is 221501665643. The next prime is 221501665757. The reversal of 221501665730 is 37566105122.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 187439641249 + 34062024481 = 432943^2 + 184559^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11075083277 + ... + 11075083296.

Almost surely, 2^221501665730 is an apocalyptic number.

221501665730 is a deficient number, since it is larger than the sum of its proper divisors (177201332602).

221501665730 is a wasteful number, since it uses less digits than its factorization.

221501665730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22150166580.

The product of its (nonzero) digits is 75600, while the sum is 38.

The spelling of 221501665730 in words is "two hundred twenty-one billion, five hundred one million, six hundred sixty-five thousand, seven hundred thirty".