381225816 has 96 divisors (see below), whose sum is σ = 1097984160. Its totient is φ = 119079936.

The previous prime is 381225809. The next prime is 381225827. The reversal of 381225816 is 618522183.

It is a happy number.

381225816 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 358101 + ... + 359163.

It is an arithmetic number, because the mean of its divisors is an integer number (11437335).

Almost surely, 2^381225816 is an apocalyptic number.

381225816 is a gapful number since it is divisible by the number (36) 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 381225816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (548992080).

381225816 is an abundant number, since it is smaller than the sum of its proper divisors (716758344).

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

381225816 is a wasteful number, since it uses less digits than its factorization.

381225816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1385 (or 1378 counting only the distinct ones).

The product of its digits is 23040, while the sum is 36.

The square root of 381225816 is about 19525.0048911646. The cubic root of 381225816 is about 725.0936484657.

Adding to 381225816 its reverse (618522183), we get a palindrome (999747999).

The spelling of 381225816 in words is "three hundred eighty-one million, two hundred twenty-five thousand, eight hundred sixteen".