221555480 has 16 divisors (see below), whose sum is σ = 498499920. Its totient is φ = 88622176.

The previous prime is 221555473. The next prime is 221555491. The reversal of 221555480 is 84555122.

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, 2769404 + ... + 2769483.

It is an arithmetic number, because the mean of its divisors is an integer number (31156245).

Almost surely, 2^221555480 is an apocalyptic number.

221555480 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221555480 is an abundant number, since it is smaller than the sum of its proper divisors (276944440).

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

221555480 is a wasteful number, since it uses less digits than its factorization.

221555480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5538898 (or 5538894 counting only the distinct ones).

The product of its (nonzero) digits is 16000, while the sum is 32.

The square root of 221555480 is about 14884.7398364903. The cubic root of 221555480 is about 605.1004819103.

The spelling of 221555480 in words is "two hundred twenty-one million, five hundred fifty-five thousand, four hundred eighty".