381406644 has 30 divisors (see below), whose sum is σ = 997073154. Its totient is φ = 127135440.

The previous prime is 381406607. The next prime is 381406657. The reversal of 381406644 is 446604183.

381406644 is a `hidden beast` number, since 3 + 8 + 1 + 4 + 0 + 6 + 644 = 666.

It can be written as a sum of positive squares in only one way, i.e., 343731600 + 37675044 = 18540^2 + 6138^2 .

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 = 381406599 and 381406608.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 588267 + ... + 588914.

Almost surely, 2^381406644 is an apocalyptic number.

It is an amenable number.

381406644 is an abundant number, since it is smaller than the sum of its proper divisors (615666510).

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

381406644 is a wasteful number, since it uses less digits than its factorization.

381406644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1177197 (or 1177186 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 36.

The square root of 381406644 is about 19529.6350196311. The cubic root of 381406644 is about 725.2082756352.

The spelling of 381406644 in words is "three hundred eighty-one million, four hundred six thousand, six hundred forty-four".