381813880 has 128 divisors (see below), whose sum is σ = 1061424000. Its totient is φ = 123131904.

The previous prime is 381813833. The next prime is 381813881. The reversal of 381813880 is 88318183.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (381813881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 232422 + ... + 234058.

It is an arithmetic number, because the mean of its divisors is an integer number (8292375).

Almost surely, 2^381813880 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 381813880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (530712000).

381813880 is an abundant number, since it is smaller than the sum of its proper divisors (679610120).

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

381813880 is a wasteful number, since it uses less digits than its factorization.

381813880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1686 (or 1668 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 40.

The square root of 381813880 is about 19540.0583417757. The cubic root of 381813880 is about 725.4662906033.

The spelling of 381813880 in words is "three hundred eighty-one million, eight hundred thirteen thousand, eight hundred eighty".