3921831309 has 12 divisors (see below), whose sum is σ = 5747698208. Its totient is φ = 2376867240.

The previous prime is 3921831299. The next prime is 3921831349. The reversal of 3921831309 is 9031381293.

3921831309 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 3921831309 - 2¹⁵ = 3921798541 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3921831349) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5401609 + ... + 5402334.

Almost surely, 2^3921831309 is an apocalyptic number.

It is an amenable number.

3921831309 is a deficient number, since it is larger than the sum of its proper divisors (1825866899).

3921831309 is a wasteful number, since it uses less digits than its factorization.

3921831309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10803968 (or 10803957 counting only the distinct ones).

The product of its (nonzero) digits is 34992, while the sum is 39.

The square root of 3921831309 is about 62624.5264173710. The cubic root of 3921831309 is about 1576.9925310475.

The spelling of 3921831309 in words is "three billion, nine hundred twenty-one million, eight hundred thirty-one thousand, three hundred nine".