221659840 has 112 divisors (see below), whose sum is σ = 549188640. Its totient is φ = 85155840.

The previous prime is 221659813. The next prime is 221659853. The reversal of 221659840 is 48956122.

It is a self number, because there is not a number n which added to its sum of digits gives 221659840.

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 15 ways as a sum of consecutive naturals, for example, 1224550 + ... + 1224730.

It is an arithmetic number, because the mean of its divisors is an integer number (4903470).

Almost surely, 2^221659840 is an apocalyptic number.

221659840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221659840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (274594320).

221659840 is an abundant number, since it is smaller than the sum of its proper divisors (327528800).

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

221659840 is a wasteful number, since it uses less digits than its factorization.

221659840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 330 (or 320 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 37.

The square root of 221659840 is about 14888.2450275377. The cubic root of 221659840 is about 605.1954744811.

The spelling of 221659840 in words is "two hundred twenty-one million, six hundred fifty-nine thousand, eight hundred forty".