3931009 has 4 divisors (see below), whose sum is σ = 3934980. Its totient is φ = 3927040.

The previous prime is 3931001. The next prime is 3931027. The reversal of 3931009 is 9001393.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 9001393 = 47 ⋅191519.

It can be written as a sum of positive squares in 2 ways, for example, as 1690000 + 2241009 = 1300^2 + 1497^2 .

It is a cyclic number.

It is not a de Polignac number, because 3931009 - 2³ = 3931001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3931001) 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, 849 + ... + 2929.

It is an arithmetic number, because the mean of its divisors is an integer number (983745).

Almost surely, 2^3931009 is an apocalyptic number.

It is an amenable number.

3931009 is a deficient number, since it is larger than the sum of its proper divisors (3971).

3931009 is a wasteful number, since it uses less digits than its factorization.

3931009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3970.

The product of its (nonzero) digits is 729, while the sum is 25.

The square root of 3931009 is about 1982.6772304135. The cubic root of 3931009 is about 157.8221708089.

The spelling of 3931009 in words is "three million, nine hundred thirty-one thousand, nine".