3957021 has 12 divisors (see below), whose sum is σ = 5913180. Its totient is φ = 2546880.

The previous prime is 3957017. The next prime is 3957047. The reversal of 3957021 is 1207593.

3957021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 2134521 + 1822500 = 1461^2 + 1350^2 .

It is not a de Polignac number, because 3957021 - 2² = 3957017 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3957091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7320 + ... + 7841.

It is an arithmetic number, because the mean of its divisors is an integer number (492765).

Almost surely, 2^3957021 is an apocalyptic number.

It is an amenable number.

3957021 is a deficient number, since it is larger than the sum of its proper divisors (1956159).

3957021 is a wasteful number, since it uses less digits than its factorization.

3957021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15196 (or 15193 counting only the distinct ones).

The product of its (nonzero) digits is 1890, while the sum is 27.

The square root of 3957021 is about 1989.2262314780. The cubic root of 3957021 is about 158.1695157621.

The spelling of 3957021 in words is "three million, nine hundred fifty-seven thousand, twenty-one".