3971649 has 16 divisors (see below), whose sum is σ = 5874624. Its totient is φ = 2366400.

The previous prime is 3971621. The next prime is 3971651. The reversal of 3971649 is 9461793.

It is not a de Polignac number, because 3971649 - 2⁸ = 3971393 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3971549) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1027 + ... + 2999.

It is an arithmetic number, because the mean of its divisors is an integer number (367164).

Almost surely, 2^3971649 is an apocalyptic number.

It is an amenable number.

3971649 is a deficient number, since it is larger than the sum of its proper divisors (1902975).

3971649 is a wasteful number, since it uses less digits than its factorization.

3971649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2048.

The product of its digits is 40824, while the sum is 39.

The square root of 3971649 is about 1992.8996462441. The cubic root of 3971649 is about 158.3641789089.

The spelling of 3971649 in words is "three million, nine hundred seventy-one thousand, six hundred forty-nine".