381281813864 has 256 divisors, whose sum is σ = 929129978880. Its totient is φ = 142859059200.

The previous prime is 381281813863. The next prime is 381281813873. The reversal of 381281813864 is 468318182183.

It is a super-2 number, since 2×381281813864² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (53).

Its product of digits (1769472) is a multiple of the sum of its prime divisors (3456).

It is not an unprimeable number, because it can be changed into a prime (381281813863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 117207662 + ... + 117210914.

It is an arithmetic number, because the mean of its divisors is an integer number (3629413980).

Almost surely, 2^381281813864 is an apocalyptic number.

381281813864 is a gapful number since it is divisible by the number (34) 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 381281813864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (464564989440).

381281813864 is an abundant number, since it is smaller than the sum of its proper divisors (547848165016).

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

381281813864 is a wasteful number, since it uses less digits than its factorization.

381281813864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3460 (or 3456 counting only the distinct ones).

The product of its digits is 1769472, while the sum is 53.

The spelling of 381281813864 in words is "three hundred eighty-one billion, two hundred eighty-one million, eight hundred thirteen thousand, eight hundred sixty-four".