3865971787840 has 224 divisors, whose sum is σ = 9731008224000. Its totient is φ = 1458869501952.

The previous prime is 3865971787831. The next prime is 3865971787871. The reversal of 3865971787840 is 487871795683.

It is a super-3 number, since 3×3865971787840³ (a number of 39 digits) contains 333 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2046569616 + ... + 2046571504.

It is an arithmetic number, because the mean of its divisors is an integer number (43442001000).

Almost surely, 2^{3865971787840} 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 3865971787840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4865504112000).

3865971787840 is an abundant number, since it is smaller than the sum of its proper divisors (5865036436160).

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

3865971787840 is a wasteful number, since it uses less digits than its factorization.

3865971787840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3157 (or 3147 counting only the distinct ones).

The product of its (nonzero) digits is 568995840, while the sum is 73.

The spelling of 3865971787840 in words is "three trillion, eight hundred sixty-five billion, nine hundred seventy-one million, seven hundred eighty-seven thousand, eight hundred forty".