3957840 has 120 divisors (see below), whose sum is σ = 13927680. Its totient is φ = 1005312.

The previous prime is 3957839. The next prime is 3957847. The reversal of 3957840 is 487593.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 3957795 and 3957804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3957847) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16441 + ... + 16679.

It is an arithmetic number, because the mean of its divisors is an integer number (116064).

Almost surely, 2^3957840 is an apocalyptic number.

3957840 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3957840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6963840).

3957840 is an abundant number, since it is smaller than the sum of its proper divisors (9969840).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3957840 is a wasteful number, since it uses less digits than its factorization.

3957840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 281 (or 272 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 3957840 is about 1989.4320797655. The cubic root of 3957840 is about 158.1804273290.

The spelling of 3957840 in words is "three million, nine hundred fifty-seven thousand, eight hundred forty".