220908821 has 16 divisors (see below), whose sum is σ = 261381120. Its totient is φ = 182701440.

The previous prime is 220908811. The next prime is 220908851. The reversal of 220908821 is 128809022.

220908821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 220908821 - 2⁶ = 220908757 is a prime.

It is a super-2 number, since 2×220908821² = 97601414391220082, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (220908811) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 83105 + ... + 85721.

It is an arithmetic number, because the mean of its divisors is an integer number (16336320).

Almost surely, 2^220908821 is an apocalyptic number.

It is an amenable number.

220908821 is a deficient number, since it is larger than the sum of its proper divisors (40472299).

220908821 is a wasteful number, since it uses less digits than its factorization.

220908821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3044.

The product of its (nonzero) digits is 4608, while the sum is 32.

The square root of 220908821 is about 14863.0017493103. The cubic root of 220908821 is about 604.5112013930.

The spelling of 220908821 in words is "two hundred twenty million, nine hundred eight thousand, eight hundred twenty-one".