3956509 has 2 divisors, whose sum is σ = 3956510. Its totient is φ = 3956508.

The previous prime is 3956501. The next prime is 3956543. The reversal of 3956509 is 9056593.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1988100 + 1968409 = 1410^2 + 1403^2 .

It is a cyclic number.

It is not a de Polignac number, because 3956509 - 2³ = 3956501 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3956501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1978254 + 1978255.

It is an arithmetic number, because the mean of its divisors is an integer number (1978255).

Almost surely, 2^3956509 is an apocalyptic number.

It is an amenable number.

3956509 is a deficient number, since it is larger than the sum of its proper divisors (1).

3956509 is an equidigital number, since it uses as much as digits as its factorization.

3956509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36450, while the sum is 37.

The square root of 3956509 is about 1989.0975340591. The cubic root of 3956509 is about 158.1626936026.

It can be divided in two parts, 3956 and 509, that added together give a triangular number (4465 = T₉₄).

The spelling of 3956509 in words is "three million, nine hundred fifty-six thousand, five hundred nine".