2221688 has 32 divisors (see below), whose sum is σ = 4821600. Its totient is φ = 940032.

The previous prime is 2221673. The next prime is 2221699. The reversal of 2221688 is 8861222.

2221688 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 2221688.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 5228 + ... + 5636.

It is an arithmetic number, because the mean of its divisors is an integer number (150675).

2^2221688 is an apocalyptic number.

2221688 is a gapful number since it is divisible by the number (28) 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 2221688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2410800).

2221688 is an abundant number, since it is smaller than the sum of its proper divisors (2599912).

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

2221688 is a wasteful number, since it uses less digits than its factorization.

2221688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 519 (or 515 counting only the distinct ones).

The product of its digits is 3072, while the sum is 29.

The square root of 2221688 is about 1490.5327906490. The cubic root of 2221688 is about 130.4851301544.

The spelling of 2221688 in words is "two million, two hundred twenty-one thousand, six hundred eighty-eight".