2201721 has 16 divisors (see below), whose sum is σ = 3245184. Its totient is φ = 1320704.

The previous prime is 2201711. The next prime is 2201723. The reversal of 2201721 is 1271022.

It is a cyclic number.

It is not a de Polignac number, because 2201721 - 2⁹ = 2201209 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2201721.

It is not an unprimeable number, because it can be changed into a prime (2201723) 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, 235 + ... + 2111.

It is an arithmetic number, because the mean of its divisors is an integer number (202824).

2^2201721 is an apocalyptic number.

It is an amenable number.

2201721 is a deficient number, since it is larger than the sum of its proper divisors (1043463).

2201721 is a wasteful number, since it uses less digits than its factorization.

2201721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1920.

The product of its (nonzero) digits is 56, while the sum is 15.

The square root of 2201721 is about 1483.8197329865. The cubic root of 2201721 is about 130.0930497529.

Adding to 2201721 its reverse (1271022), we get a palindrome (3472743).

The spelling of 2201721 in words is "two million, two hundred one thousand, seven hundred twenty-one".