3866581840 has 80 divisors (see below), whose sum is σ = 9820621440. Its totient is φ = 1404085760.

The previous prime is 3866581781. The next prime is 3866581841. The reversal of 3866581840 is 481856683.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3866581841) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 735702 + ... + 740938.

It is an arithmetic number, because the mean of its divisors is an integer number (122757768).

Almost surely, 2^3866581840 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 3866581840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4910310720).

3866581840 is an abundant number, since it is smaller than the sum of its proper divisors (5954039600).

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

3866581840 is a wasteful number, since it uses less digits than its factorization.

3866581840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6100 (or 6094 counting only the distinct ones).

The product of its (nonzero) digits is 1105920, while the sum is 49.

The square root of 3866581840 is about 62181.8449388566. The cubic root of 3866581840 is about 1569.5520974732.

The spelling of 3866581840 in words is "three billion, eight hundred sixty-six million, five hundred eighty-one thousand, eight hundred forty".