221764730 has 32 divisors (see below), whose sum is σ = 436140288. Its totient is φ = 80516800.

The previous prime is 221764727. The next prime is 221764747. The reversal of 221764730 is 37467122.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 99104 + ... + 101316.

It is an arithmetic number, because the mean of its divisors is an integer number (13629384).

Almost surely, 2^221764730 is an apocalyptic number.

221764730 is a deficient number, since it is larger than the sum of its proper divisors (214375558).

221764730 is a wasteful number, since it uses less digits than its factorization.

221764730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3142.

The product of its (nonzero) digits is 14112, while the sum is 32.

The square root of 221764730 is about 14891.7671886180. The cubic root of 221764730 is about 605.2909194403.

The spelling of 221764730 in words is "two hundred twenty-one million, seven hundred sixty-four thousand, seven hundred thirty".