221505066 has 24 divisors (see below), whose sum is σ = 480679524. Its totient is φ = 73719360.

The previous prime is 221505049. The next prime is 221505077. The reversal of 221505066 is 660505122.

221505066 is a `hidden beast` number, since 2 + 2 + 150 + 506 + 6 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 176225625 + 45279441 = 13275^2 + 6729^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2590 + ... + 21206.

Almost surely, 2^221505066 is an apocalyptic number.

221505066 is an abundant number, since it is smaller than the sum of its proper divisors (259174458).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221505066 is a wasteful number, since it uses less digits than its factorization.

221505066 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19286 (or 19283 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 221505066 is about 14883.0462607626. The cubic root of 221505066 is about 605.0545824215.

The spelling of 221505066 in words is "two hundred twenty-one million, five hundred five thousand, sixty-six".