221487680 has 28 divisors (see below), whose sum is σ = 527418300. Its totient is φ = 88594944.

The previous prime is 221487667. The next prime is 221487697. The reversal of 221487680 is 86784122.

It can be written as a sum of positive squares in 2 ways, for example, as 164454976 + 57032704 = 12824^2 + 7552^2 .

It is a hoax number, since the sum of its digits (38) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 345755 + ... + 346394.

Almost surely, 2^221487680 is an apocalyptic number.

221487680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221487680 is an abundant number, since it is smaller than the sum of its proper divisors (305930620).

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

221487680 is an equidigital number, since it uses as much as digits as its factorization.

221487680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 692166 (or 692156 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 38.

The square root of 221487680 is about 14882.4621618871. The cubic root of 221487680 is about 605.0387517013.

The spelling of 221487680 in words is "two hundred twenty-one million, four hundred eighty-seven thousand, six hundred eighty".