3981920 has 48 divisors (see below), whose sum is σ = 9652608. Its totient is φ = 1551360.

The previous prime is 3981917. The next prime is 3981937. The reversal of 3981920 is 291893.

3981920 is nontrivially palindromic in base 3.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6257 + ... + 6863.

It is an arithmetic number, because the mean of its divisors is an integer number (201096).

Almost surely, 2^3981920 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3981920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4826304).

3981920 is an abundant number, since it is smaller than the sum of its proper divisors (5670688).

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

3981920 is a wasteful number, since it uses less digits than its factorization.

3981920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 663 (or 655 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 32.

The square root of 3981920 is about 1995.4748808241. The cubic root of 3981920 is about 158.5005755170.

The spelling of 3981920 in words is "three million, nine hundred eighty-one thousand, nine hundred twenty".