3720209 has 2 divisors, whose sum is σ = 3720210. Its totient is φ = 3720208.

The previous prime is 3720179. The next prime is 3720247. The reversal of 3720209 is 9020273.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3717184 + 3025 = 1928^2 + 55^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3720209 is a prime.

It is not a weakly prime, because it can be changed into another prime (3710209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1860104 + 1860105.

It is an arithmetic number, because the mean of its divisors is an integer number (1860105).

Almost surely, 2^3720209 is an apocalyptic number.

It is an amenable number.

3720209 is a deficient number, since it is larger than the sum of its proper divisors (1).

3720209 is an equidigital number, since it uses as much as digits as its factorization.

3720209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 756, while the sum is 23.

The square root of 3720209 is about 1928.7843321637. The cubic root of 3720209 is about 154.9491196161.

The spelling of 3720209 in words is "three million, seven hundred twenty thousand, two hundred nine".