221478768 has 60 divisors (see below), whose sum is σ = 708383728. Its totient is φ = 63279360.

The previous prime is 221478731. The next prime is 221478773. The reversal of 221478768 is 867874122.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 108853 + ... + 110868.

Almost surely, 2^221478768 is an apocalyptic number.

221478768 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

221478768 is an abundant number, since it is smaller than the sum of its proper divisors (486904960).

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

221478768 is a wasteful number, since it uses less digits than its factorization.

221478768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 219742 (or 219733 counting only the distinct ones).

The product of its digits is 301056, while the sum is 45.

The square root of 221478768 is about 14882.1627460527. The cubic root of 221478768 is about 605.0306366108.

The spelling of 221478768 in words is "two hundred twenty-one million, four hundred seventy-eight thousand, seven hundred sixty-eight".