3981220 has 24 divisors (see below), whose sum is σ = 8427384. Its totient is φ = 1579776.

The previous prime is 3981217. The next prime is 3981227. The reversal of 3981220 is 221893.

It can be written as a sum of positive squares in 4 ways, for example, as 1572516 + 2408704 = 1254^2 + 1552^2 .

It is a super-2 number, since 2×3981220² = 31700225376800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (3981227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2014 + ... + 3466.

It is an arithmetic number, because the mean of its divisors is an integer number (351141).

Almost surely, 2^3981220 is an apocalyptic number.

It is an amenable number.

3981220 is an abundant number, since it is smaller than the sum of its proper divisors (4446164).

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

3981220 is a wasteful number, since it uses less digits than its factorization.

3981220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1599 (or 1597 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 3981220 is about 1995.2994762692. The cubic root of 3981220 is about 158.4912871247.

The spelling of 3981220 in words is "three million, nine hundred eighty-one thousand, two hundred twenty".