221255560 has 32 divisors (see below), whose sum is σ = 511283160. Its totient is φ = 86109696.

The previous prime is 221255543. The next prime is 221255569. The reversal of 221255560 is 65552122.

It can be written as a sum of positive squares in 4 ways, for example, as 184362084 + 36893476 = 13578^2 + 6074^2 .

It is not an unprimeable number, because it can be changed into a prime (221255569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 73269 + ... + 76228.

Almost surely, 2^221255560 is an apocalyptic number.

221255560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221255560 is an abundant number, since it is smaller than the sum of its proper divisors (290027600).

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

221255560 is a wasteful number, since it uses less digits than its factorization.

221255560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149545 (or 149541 counting only the distinct ones).

The product of its (nonzero) digits is 6000, while the sum is 28.

The square root of 221255560 is about 14874.6616768248. The cubic root of 221255560 is about 604.8273167887.

The spelling of 221255560 in words is "two hundred twenty-one million, two hundred fifty-five thousand, five hundred sixty".