381009840 has 160 divisors (see below), whose sum is σ = 1235920896. Its totient is φ = 96983040.

The previous prime is 381009829. The next prime is 381009847. The reversal of 381009840 is 48900183.

It is not an unprimeable number, because it can be changed into a prime (381009847) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 617212 + ... + 617828.

Almost surely, 2^381009840 is an apocalyptic number.

381009840 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 381009840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (617960448).

381009840 is an abundant number, since it is smaller than the sum of its proper divisors (854911056).

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

381009840 is a wasteful number, since it uses less digits than its factorization.

381009840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 747 (or 741 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 33.

The square root of 381009840 is about 19519.4733535513. The cubic root of 381009840 is about 724.9566934100.

The spelling of 381009840 in words is "three hundred eighty-one million, nine thousand, eight hundred forty".