3981540420 has 576 divisors, whose sum is σ = 15626048256. Its totient is φ = 836075520.

The previous prime is 3981540391. The next prime is 3981540427. The reversal of 3981540420 is 240451893.

3981540420 is a `hidden beast` number, since 3 + 98 + 1 + 540 + 4 + 20 = 666.

3981540420 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not an unprimeable number, because it can be changed into a prime (3981540427) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 11814492 + ... + 11814828.

It is an arithmetic number, because the mean of its divisors is an integer number (27128556).

Almost surely, 2^3981540420 is an apocalyptic number.

3981540420 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 3981540420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7813024128).

3981540420 is an abundant number, since it is smaller than the sum of its proper divisors (11644507836).

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

3981540420 is a wasteful number, since it uses less digits than its factorization.

3981540420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 402 (or 388 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 3981540420 is about 63099.4486505231. The cubic root of 3981540420 is about 1584.9553895501.

The spelling of 3981540420 in words is "three billion, nine hundred eighty-one million, five hundred forty thousand, four hundred twenty".