381940 has 36 divisors (see below), whose sum is σ = 876204. Its totient is φ = 139776.

The previous prime is 381937. The next prime is 381943. The reversal of 381940 is 49183.

381940 = T₁₂₀ + T₁₂₁ + ... + T₁₅₈.

It is an interprime number because it is at equal distance from previous prime (381937) and next prime (381943).

It can be written as a sum of positive squares in 6 ways, for example, as 191844 + 190096 = 438^2 + 436^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (381943) 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, 3324 + ... + 3436.

It is an arithmetic number, because the mean of its divisors is an integer number (24339).

2³⁸¹⁹⁴⁰ 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 381940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (438102).

381940 is an abundant number, since it is smaller than the sum of its proper divisors (494264).

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

381940 is a wasteful number, since it uses less digits than its factorization.

381940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148 (or 133 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 381940 is about 618.0129448482. The cubic root of 381940 is about 72.5546160003.

The spelling of 381940 in words is "three hundred eighty-one thousand, nine hundred forty".