6381918 has 12 divisors (see below), whose sum is σ = 13827528. Its totient is φ = 2127300.

The previous prime is 6381913. The next prime is 6381941. The reversal of 6381918 is 8191836.

6381918 is a `hidden beast` number, since 638 + 1 + 9 + 18 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6381911) 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 5 ways as a sum of consecutive naturals, for example, 177258 + ... + 177293.

It is an arithmetic number, because the mean of its divisors is an integer number (1152294).

Almost surely, 2^6381918 is an apocalyptic number.

6381918 is an abundant number, since it is smaller than the sum of its proper divisors (7445610).

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

6381918 is a wasteful number, since it uses less digits than its factorization.

6381918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 354559 (or 354556 counting only the distinct ones).

The product of its digits is 10368, while the sum is 36.

The square root of 6381918 is about 2526.2458312682. The cubic root of 6381918 is about 185.4885358952.

It can be divided in two parts, 638 and 1918, that added together give a triangular number (2556 = T₇₁).

The spelling of 6381918 in words is "six million, three hundred eighty-one thousand, nine hundred eighteen".