381771920 has 80 divisors (see below), whose sum is σ = 921356208. Its totient is φ = 146995200.

The previous prime is 381771911. The next prime is 381771953. The reversal of 381771920 is 29177183.

It can be written as a sum of positive squares in 8 ways, for example, as 97377424 + 284394496 = 9868^2 + 16864^2 .

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 298322 + ... + 299598.

Almost surely, 2^381771920 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 381771920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (460678104).

381771920 is an abundant number, since it is smaller than the sum of its proper divisors (539584288).

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

381771920 is a wasteful number, since it uses less digits than its factorization.

381771920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1428 (or 1422 counting only the distinct ones).

The product of its (nonzero) digits is 21168, while the sum is 38.

The square root of 381771920 is about 19538.9846204965. The cubic root of 381771920 is about 725.4397142334.

The spelling of 381771920 in words is "three hundred eighty-one million, seven hundred seventy-one thousand, nine hundred twenty".