3709509 has 16 divisors (see below), whose sum is σ = 5304192. Its totient is φ = 2299968.

The previous prime is 3709501. The next prime is 3709513. The reversal of 3709509 is 9059073.

It is not a de Polignac number, because 3709509 - 2³ = 3709501 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 3709509.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3709501) 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, 1827 + ... + 3279.

It is an arithmetic number, because the mean of its divisors is an integer number (331512).

Almost surely, 2^3709509 is an apocalyptic number.

It is an amenable number.

3709509 is a deficient number, since it is larger than the sum of its proper divisors (1594683).

3709509 is a wasteful number, since it uses less digits than its factorization.

3709509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1516.

The product of its (nonzero) digits is 8505, while the sum is 33.

The square root of 3709509 is about 1926.0085669591. The cubic root of 3709509 is about 154.8004229836.

Subtracting from 3709509 its sum of digits (33), we obtain a square (3709476 = 1926²).

It can be divided in two parts, 3709 and 509, that multiplied together give a palindrome (1887881).

The spelling of 3709509 in words is "three million, seven hundred nine thousand, five hundred nine".