3978720 has 120 divisors (see below), whose sum is σ = 14087304. Its totient is φ = 1057536.

The previous prime is 3978707. The next prime is 3978727. The reversal of 3978720 is 278793.

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 congruent number.

It is not an unprimeable number, because it can be changed into a prime (3978727) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 12807 + ... + 13113.

Almost surely, 2^3978720 is an apocalyptic number.

3978720 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 3978720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7043652).

3978720 is an abundant number, since it is smaller than the sum of its proper divisors (10108584).

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

3978720 is a wasteful number, since it uses less digits than its factorization.

3978720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 334 (or 317 counting only the distinct ones).

The product of its (nonzero) digits is 21168, while the sum is 36.

The square root of 3978720 is about 1994.6729055161. The cubic root of 3978720 is about 158.4581054045.

The spelling of 3978720 in words is "three million, nine hundred seventy-eight thousand, seven hundred twenty".