381831866 has 48 divisors (see below), whose sum is σ = 689558184. Its totient is φ = 157068288.

The previous prime is 381831851. The next prime is 381831871. The reversal of 381831866 is 668138183.

It can be written as a sum of positive squares in 4 ways, for example, as 200364025 + 181467841 = 14155^2 + 13471^2 .

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, 158366 + ... + 160758.

Almost surely, 2^381831866 is an apocalyptic number.

381831866 is a deficient number, since it is larger than the sum of its proper divisors (307726318).

381831866 is a wasteful number, since it uses less digits than its factorization.

381831866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2463 (or 2444 counting only the distinct ones).

The product of its digits is 165888, while the sum is 44.

The square root of 381831866 is about 19540.5185703962. The cubic root of 381831866 is about 725.4776818705.

The spelling of 381831866 in words is "three hundred eighty-one million, eight hundred thirty-one thousand, eight hundred sixty-six".