3855840 has 96 divisors (see below), whose sum is σ = 12610080. Its totient is φ = 989184.

The previous prime is 3855829. The next prime is 3855851. The reversal of 3855840 is 485583.

3855840 = T₂₄ + T₂₅ + ... + T₂₈₄.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (3855829) and next prime (3855851).

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13782 + ... + 14058.

It is an arithmetic number, because the mean of its divisors is an integer number (131355).

Almost surely, 2^3855840 is an apocalyptic number.

3855840 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 3855840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6305040).

3855840 is an abundant number, since it is smaller than the sum of its proper divisors (8754240).

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

3855840 is a wasteful number, since it uses less digits than its factorization.

3855840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 324 (or 316 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 33.

The square root of 3855840 is about 1963.6292929166. The cubic root of 3855840 is about 156.8097279818.

The spelling of 3855840 in words is "three million, eight hundred fifty-five thousand, eight hundred forty".