2066721 has 4 divisors (see below), whose sum is σ = 2755632. Its totient is φ = 1377812.

The previous prime is 2066717. The next prime is 2066723. The reversal of 2066721 is 1276602.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2066721 - 2² = 2066717 is a prime.

It is a D-number.

It is a junction number, because it is equal to n+sod(n) for n = 2066691 and 2066700.

It is not an unprimeable number, because it can be changed into a prime (2066723) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 344451 + ... + 344456.

It is an arithmetic number, because the mean of its divisors is an integer number (688908).

2^2066721 is an apocalyptic number.

It is an amenable number.

2066721 is a deficient number, since it is larger than the sum of its proper divisors (688911).

2066721 is an equidigital number, since it uses as much as digits as its factorization.

2066721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 688910.

The product of its (nonzero) digits is 1008, while the sum is 24.

The square root of 2066721 is about 1437.6094740923. The cubic root of 2066721 is about 127.3778607343.

The spelling of 2066721 in words is "two million, sixty-six thousand, seven hundred twenty-one".