381531393 has 12 divisors (see below), whose sum is σ = 560136148. Its totient is φ = 250184160.

The previous prime is 381531377. The next prime is 381531401. The reversal of 381531393 is 393135183.

It is a happy number.

381531393 is a `hidden beast` number, since 38 + 1 + 531 + 3 + 93 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 63872064 + 317659329 = 7992^2 + 17823^2 .

It is not a de Polignac number, because 381531393 - 2⁴ = 381531377 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (381531193) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 346930 + ... + 348027.

Almost surely, 2^381531393 is an apocalyptic number.

It is an amenable number.

381531393 is a deficient number, since it is larger than the sum of its proper divisors (178604755).

381531393 is a wasteful number, since it uses less digits than its factorization.

381531393 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 695024 (or 695021 counting only the distinct ones).

The product of its digits is 29160, while the sum is 36.

The square root of 381531393 is about 19532.8285970056. The cubic root of 381531393 is about 725.2873331162.

It can be divided in two parts, 381531 and 393, that added together give a square (381924 = 618²).

The spelling of 381531393 in words is "three hundred eighty-one million, five hundred thirty-one thousand, three hundred ninety-three".