381550 has 24 divisors (see below), whose sum is σ = 765576. Its totient is φ = 140640.

The previous prime is 381541. The next prime is 381559. The reversal of 381550 is 55183.

It is an interprime number because it is at equal distance from previous prime (381541) and next prime (381559).

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (381559) by changing a digit.

381550 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 11 ways as a sum of consecutive naturals, for example, 357 + ... + 943.

It is an arithmetic number, because the mean of its divisors is an integer number (31899).

2³⁸¹⁵⁵⁰ is an apocalyptic number.

381550 is an abundant number, since it is smaller than the sum of its proper divisors (384026).

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

381550 is a wasteful number, since it uses less digits than its factorization.

381550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 612 (or 607 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 381550 is about 617.6973368892. The cubic root of 381550 is about 72.5299123498.

It can be divided in two parts, 3 and 81550, that multiplied together give a triangular number (244650 = T₆₉₉).

The spelling of 381550 in words is "three hundred eighty-one thousand, five hundred fifty".