381520 has 40 divisors (see below), whose sum is σ = 937440. Its totient is φ = 144000.

The previous prime is 381509. The next prime is 381523. The reversal of 381520 is 25183.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (381523) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1395 + ... + 1645.

It is an arithmetic number, because the mean of its divisors is an integer number (23436).

2³⁸¹⁵²⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 381520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (468720).

381520 is an abundant number, since it is smaller than the sum of its proper divisors (555920).

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

381520 is a wasteful number, since it uses less digits than its factorization.

381520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 283 (or 277 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 381520 is about 617.6730526743. The cubic root of 381520 is about 72.5280113718.

Subtracting from 381520 its sum of digits (19), we obtain a triangular number (381501 = T₈₇₃).

The spelling of 381520 in words is "three hundred eighty-one thousand, five hundred twenty".