3881155778640 has 960 divisors, whose sum is σ = 15754991616000. Its totient is φ = 869654403072.

The previous prime is 3881155778627. The next prime is 3881155778651. The reversal of 3881155778640 is 468775511883.

3881155778640 is a `hidden beast` number, since 3 + 8 + 8 + 1 + 1 + 557 + 78 + 6 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

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, 1601796469 + ... + 1601798891.

It is an arithmetic number, because the mean of its divisors is an integer number (16411449600).

Almost surely, 2^{3881155778640} is an apocalyptic number.

3881155778640 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 3881155778640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7877495808000).

3881155778640 is an abundant number, since it is smaller than the sum of its proper divisors (11873835837360).

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

3881155778640 is a wasteful number, since it uses less digits than its factorization.

3881155778640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2686 (or 2668 counting only the distinct ones).

The product of its (nonzero) digits is 45158400, while the sum is 63.

The spelling of 3881155778640 in words is "three trillion, eight hundred eighty-one billion, one hundred fifty-five million, seven hundred seventy-eight thousand, six hundred forty".