3181909 has 4 divisors (see below), whose sum is σ = 3291660. Its totient is φ = 3072160.

The previous prime is 3181901. The next prime is 3181921. The reversal of 3181909 is 9091813.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2241009 + 940900 = 1497^2 + 970^2 .

It is a cyclic number.

It is not a de Polignac number, because 3181909 - 2³ = 3181901 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

3181909 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3181901) 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, 54832 + ... + 54889.

It is an arithmetic number, because the mean of its divisors is an integer number (822915).

Almost surely, 2^3181909 is an apocalyptic number.

It is an amenable number.

3181909 is a deficient number, since it is larger than the sum of its proper divisors (109751).

3181909 is a wasteful number, since it uses less digits than its factorization.

3181909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109750.

The product of its (nonzero) digits is 1944, while the sum is 31.

The square root of 3181909 is about 1783.7906267273. The cubic root of 3181909 is about 147.0830357530.

The spelling of 3181909 in words is "three million, one hundred eighty-one thousand, nine hundred nine".