381813444 has 72 divisors (see below), whose sum is σ = 978737760. Its totient is φ = 125494272.

The previous prime is 381813427. The next prime is 381813461. The reversal of 381813444 is 444318183.

381813444 is a `hidden beast` number, since 38 + 181 + 3 + 444 = 666.

381813444 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (381813427) and next prime (381813461).

It is a super-2 number, since 2×381813444² = 291563012038282272, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 381813399 and 381813408.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1243539 + ... + 1243845.

It is an arithmetic number, because the mean of its divisors is an integer number (13593580).

Almost surely, 2^381813444 is an apocalyptic number.

It is an amenable number.

381813444 is an abundant number, since it is smaller than the sum of its proper divisors (596924316).

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

381813444 is a wasteful number, since it uses less digits than its factorization.

381813444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 689 (or 684 counting only the distinct ones).

The product of its digits is 36864, while the sum is 36.

The square root of 381813444 is about 19540.0471852040. The cubic root of 381813444 is about 725.4660144623.

The spelling of 381813444 in words is "three hundred eighty-one million, eight hundred thirteen thousand, four hundred forty-four".