381745728 has 168 divisors, whose sum is σ = 1346899008. Its totient is φ = 100666368.

The previous prime is 381745643. The next prime is 381745729. The reversal of 381745728 is 827547183.

381745728 is a `hidden beast` number, since 3 + 8 + 1 + 74 + 572 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (168).

It is not an unprimeable number, because it can be changed into a prime (381745729) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 48775 + ... + 56057.

It is an arithmetic number, because the mean of its divisors is an integer number (8017256).

Almost surely, 2^381745728 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 381745728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (673449504).

381745728 is an abundant number, since it is smaller than the sum of its proper divisors (965153280).

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

381745728 is a wasteful number, since it uses less digits than its factorization.

381745728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7321 (or 7308 counting only the distinct ones).

The product of its digits is 376320, while the sum is 45.

The square root of 381745728 is about 19538.3143592276. The cubic root of 381745728 is about 725.4231239164.

The spelling of 381745728 in words is "three hundred eighty-one million, seven hundred forty-five thousand, seven hundred twenty-eight".