8220921 has 8 divisors (see below), whose sum is σ = 11314944. Its totient is φ = 5303760.

The previous prime is 8220899. The next prime is 8220923. The reversal of 8220921 is 1290228.

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

It is not a de Polignac number, because 8220921 - 2⁹ = 8220409 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 8220891 and 8220900.

It is not an unprimeable number, because it can be changed into a prime (8220923) 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, 44106 + ... + 44291.

It is an arithmetic number, because the mean of its divisors is an integer number (1414368).

Almost surely, 2^8220921 is an apocalyptic number.

It is an amenable number.

8220921 is a deficient number, since it is larger than the sum of its proper divisors (3094023).

8220921 is a wasteful number, since it uses less digits than its factorization.

8220921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88431.

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

The square root of 8220921 is about 2867.2148506870. The cubic root of 8220921 is about 201.8243170730.

The spelling of 8220921 in words is "eight million, two hundred twenty thousand, nine hundred twenty-one".