3721709 has 4 divisors (see below), whose sum is σ = 3737916. Its totient is φ = 3705504.

The previous prime is 3721673. The next prime is 3721717. The reversal of 3721709 is 9071273.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9071273 = 167 ⋅54319.

It can be written as a sum of positive squares in 2 ways, for example, as 1747684 + 1974025 = 1322^2 + 1405^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3721709 is a prime.

It is a super-2 number, since 2×3721709² = 27702235761362, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3721799) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7754 + ... + 8219.

It is an arithmetic number, because the mean of its divisors is an integer number (934479).

Almost surely, 2^3721709 is an apocalyptic number.

It is an amenable number.

3721709 is a deficient number, since it is larger than the sum of its proper divisors (16207).

3721709 is a wasteful number, since it uses less digits than its factorization.

3721709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16206.

The product of its (nonzero) digits is 2646, while the sum is 29.

The square root of 3721709 is about 1929.1731389380. The cubic root of 3721709 is about 154.9699421424.

The spelling of 3721709 in words is "three million, seven hundred twenty-one thousand, seven hundred nine".