2206721 has 8 divisors (see below), whose sum is σ = 2437344. Its totient is φ = 1981120.

The previous prime is 2206709. The next prime is 2206723. The reversal of 2206721 is 1276022.

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

It is a cyclic number.

It is not a de Polignac number, because 2206721 - 2⁶ = 2206657 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2206693 and 2206702.

It is not an unprimeable number, because it can be changed into a prime (2206723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 296 + ... + 2121.

It is an arithmetic number, because the mean of its divisors is an integer number (304668).

2^2206721 is an apocalyptic number.

It is an amenable number.

2206721 is a deficient number, since it is larger than the sum of its proper divisors (230623).

2206721 is a wasteful number, since it uses less digits than its factorization.

2206721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2511.

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 2206721 is about 1485.5036183059. The cubic root of 2206721 is about 130.1914536042.

The spelling of 2206721 in words is "two million, two hundred six thousand, seven hundred twenty-one".