381475728 has 30 divisors (see below), whose sum is σ = 1067602614. Its totient is φ = 127158528.

The previous prime is 381475709. The next prime is 381475751. The reversal of 381475728 is 827574183.

381475728 is a `hidden beast` number, since 38 + 1 + 47 + 572 + 8 = 666.

It can be written as a sum of positive squares in only one way, i.e., 300259584 + 81216144 = 17328^2 + 9012^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1324425 + ... + 1324712.

Almost surely, 2^381475728 is an apocalyptic number.

It is an amenable number.

381475728 is an abundant number, since it is smaller than the sum of its proper divisors (686126886).

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

381475728 is a wasteful number, since it uses less digits than its factorization.

381475728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2649151 (or 2649142 counting only the distinct ones).

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

The square root of 381475728 is about 19531.4036361957. The cubic root of 381475728 is about 725.2520585326.

The spelling of 381475728 in words is "three hundred eighty-one million, four hundred seventy-five thousand, seven hundred twenty-eight".