3931649 has 2 divisors, whose sum is σ = 3931650. Its totient is φ = 3931648.

The previous prime is 3931639. The next prime is 3931661. The reversal of 3931649 is 9461393.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3489424 + 442225 = 1868^2 + 665^2 .

It is a cyclic number.

It is not a de Polignac number, because 3931649 - 2⁸ = 3931393 is a prime.

It is not a weakly prime, because it can be changed into another prime (3931639) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1965824 + 1965825.

It is an arithmetic number, because the mean of its divisors is an integer number (1965825).

Almost surely, 2^3931649 is an apocalyptic number.

It is an amenable number.

3931649 is a deficient number, since it is larger than the sum of its proper divisors (1).

3931649 is an equidigital number, since it uses as much as digits as its factorization.

3931649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17496, while the sum is 35.

The square root of 3931649 is about 1982.8386217743. The cubic root of 3931649 is about 157.8307352519.

The spelling of 3931649 in words is "three million, nine hundred thirty-one thousand, six hundred forty-nine".