3861780216840 has 768 divisors, whose sum is σ = 16974915552000. Its totient is φ = 771906723840.

The previous prime is 3861780216797. The next prime is 3861780216937. The reversal of 3861780216840 is 486120871683.

3861780216840 is a `hidden beast` number, since 3 + 8 + 617 + 8 + 0 + 2 + 16 + 8 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 12923520 + ... + 13218960.

It is an arithmetic number, because the mean of its divisors is an integer number (22102754625).

Almost surely, 2^{3861780216840} is an apocalyptic number.

3861780216840 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 3861780216840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8487457776000).

3861780216840 is an abundant number, since it is smaller than the sum of its proper divisors (13113135335160).

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

3861780216840 is a wasteful number, since it uses less digits than its factorization.

3861780216840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 295507 (or 295490 counting only the distinct ones).

The product of its (nonzero) digits is 3096576, while the sum is 54.

The spelling of 3861780216840 in words is "three trillion, eight hundred sixty-one billion, seven hundred eighty million, two hundred sixteen thousand, eight hundred forty".