221339661 has 8 divisors (see below), whose sum is σ = 303095904. Its totient is φ = 143571600.

The previous prime is 221339653. The next prime is 221339663. The reversal of 221339661 is 166933122.

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

It is not a de Polignac number, because 221339661 - 2³ = 221339653 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221339663) by changing a digit.

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, 996915 + ... + 997136.

It is an arithmetic number, because the mean of its divisors is an integer number (37886988).

Almost surely, 2^221339661 is an apocalyptic number.

It is an amenable number.

221339661 is a deficient number, since it is larger than the sum of its proper divisors (81756243).

221339661 is a wasteful number, since it uses less digits than its factorization.

221339661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1994091.

The product of its digits is 11664, while the sum is 33.

The square root of 221339661 is about 14877.4883969036. The cubic root of 221339661 is about 604.9039403074.

The spelling of 221339661 in words is "two hundred twenty-one million, three hundred thirty-nine thousand, six hundred sixty-one".