381939840 has 384 divisors, whose sum is σ = 1458518400. Its totient is φ = 94279680.

The previous prime is 381939839. The next prime is 381939847. The reversal of 381939840 is 48939183.

It is a tau number, because it is divible by the number of its divisors (384).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (381939847) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 12320625 + ... + 12320655.

It is an arithmetic number, because the mean of its divisors is an integer number (3798225).

Almost surely, 2^381939840 is an apocalyptic number.

381939840 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 381939840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (729259200).

381939840 is an abundant number, since it is smaller than the sum of its proper divisors (1076578560).

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

381939840 is a wasteful number, since it uses less digits than its factorization.

381939840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113 (or 64 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The square root of 381939840 is about 19543.2811984068. The cubic root of 381939840 is about 725.5460586892.

The spelling of 381939840 in words is "three hundred eighty-one million, nine hundred thirty-nine thousand, eight hundred forty".