221256568 has 16 divisors (see below), whose sum is σ = 446768280. Its totient is φ = 102118368.

The previous prime is 221256533. The next prime is 221256571. The reversal of 221256568 is 865652122.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1063630 + ... + 1063837.

Almost surely, 2^221256568 is an apocalyptic number.

It is an amenable number.

221256568 is an abundant number, since it is smaller than the sum of its proper divisors (225511712).

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

221256568 is a wasteful number, since it uses less digits than its factorization.

221256568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2127486 (or 2127482 counting only the distinct ones).

The product of its digits is 57600, while the sum is 37.

The square root of 221256568 is about 14874.6955599098. The cubic root of 221256568 is about 604.8282352817.

The spelling of 221256568 in words is "two hundred twenty-one million, two hundred fifty-six thousand, five hundred sixty-eight".