221474928 has 20 divisors (see below), whose sum is σ = 572143688. Its totient is φ = 73824960.

The previous prime is 221474917. The next prime is 221474947. The reversal of 221474928 is 829474122.

It is a happy number.

It is a super-2 number, since 2×221474928² = 98102287465210368, which contains 22 as substring.

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, 2306983 + ... + 2307078.

Almost surely, 2^221474928 is an apocalyptic number.

It is an amenable number.

221474928 is an abundant number, since it is smaller than the sum of its proper divisors (350668760).

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

221474928 is a wasteful number, since it uses less digits than its factorization.

221474928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4614072 (or 4614066 counting only the distinct ones).

The product of its digits is 64512, while the sum is 39.

The square root of 221474928 is about 14882.0337319870. The cubic root of 221474928 is about 605.0271399158.

The spelling of 221474928 in words is "two hundred twenty-one million, four hundred seventy-four thousand, nine hundred twenty-eight".