221307706 has 8 divisors (see below), whose sum is σ = 349433280. Its totient is φ = 104829948.

The previous prime is 221307703. The next prime is 221307707. The reversal of 221307706 is 607703122.

221307706 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

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

It is not an unprimeable number, because it can be changed into a prime (221307703) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2911906 + ... + 2911981.

It is an arithmetic number, because the mean of its divisors is an integer number (43679160).

Almost surely, 2^221307706 is an apocalyptic number.

221307706 is a deficient number, since it is larger than the sum of its proper divisors (128125574).

221307706 is a wasteful number, since it uses less digits than its factorization.

221307706 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5823908.

The product of its (nonzero) digits is 3528, while the sum is 28.

The square root of 221307706 is about 14876.4144201484. The cubic root of 221307706 is about 604.8748287365.

The spelling of 221307706 in words is "two hundred twenty-one million, three hundred seven thousand, seven hundred six".