4001656 has 16 divisors (see below), whose sum is σ = 7527600. Its totient is φ = 1994304.

The previous prime is 4001639. The next prime is 4001689. The reversal of 4001656 is 6561004.

It is a congruent number.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 2661 + ... + 3883.

It is an arithmetic number, because the mean of its divisors is an integer number (470475).

Almost surely, 2^4001656 is an apocalyptic number.

It is an amenable number.

4001656 is a deficient number, since it is larger than the sum of its proper divisors (3525944).

4001656 is a wasteful number, since it uses less digits than its factorization.

4001656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1638 (or 1634 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 4001656 is about 2000.4139571599. The cubic root of 4001656 is about 158.7620083090.

The spelling of 4001656 in words is "four million, one thousand, six hundred fifty-six".