9220821 has 8 divisors (see below), whose sum is σ = 12496224. Its totient is φ = 6046320.

The previous prime is 9220793. The next prime is 9220829. The reversal of 9220821 is 1280229.

9220821 is digitally balanced in base 2, base 3 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 9220821 - 2⁷ = 9220693 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 9220791 and 9220800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9220829) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25011 + ... + 25376.

It is an arithmetic number, because the mean of its divisors is an integer number (1562028).

Almost surely, 2^9220821 is an apocalyptic number.

It is an amenable number.

9220821 is a deficient number, since it is larger than the sum of its proper divisors (3275403).

9220821 is a wasteful number, since it uses less digits than its factorization.

9220821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50451.

The product of its (nonzero) digits is 576, while the sum is 24.

The square root of 9220821 is about 3036.5804781036. The cubic root of 9220821 is about 209.6958635963.

It can be divided in two parts, 92208 and 21, that added together give a palindrome (92229).

The spelling of 9220821 in words is "nine million, two hundred twenty thousand, eight hundred twenty-one".