381820188 has 12 divisors (see below), whose sum is σ = 890913800. Its totient is φ = 127273392.

The previous prime is 381820183. The next prime is 381820189. The reversal of 381820188 is 881028183.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (381820183) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15909163 + ... + 15909186.

Almost surely, 2^381820188 is an apocalyptic number.

It is an amenable number.

381820188 is an abundant number, since it is smaller than the sum of its proper divisors (509093612).

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

381820188 is a wasteful number, since it uses less digits than its factorization.

381820188 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31818356 (or 31818354 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 39.

The square root of 381820188 is about 19540.2197531143. The cubic root of 381820188 is about 725.4702857576.

The spelling of 381820188 in words is "three hundred eighty-one million, eight hundred twenty thousand, one hundred eighty-eight".