381564 has 24 divisors (see below), whose sum is σ = 989520. Its totient is φ = 127152.

The previous prime is 381559. The next prime is 381569. The reversal of 381564 is 465183.

It is an interprime number because it is at equal distance from previous prime (381559) and next prime (381569).

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 381564.

It is not an unprimeable number, because it can be changed into a prime (381569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1659 + ... + 1874.

It is an arithmetic number, because the mean of its divisors is an integer number (41230).

2³⁸¹⁵⁶⁴ is an apocalyptic number.

It is an amenable number.

381564 is an abundant number, since it is smaller than the sum of its proper divisors (607956).

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

381564 is a wasteful number, since it uses less digits than its factorization.

381564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3546 (or 3538 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 381564 is about 617.7086691961. The cubic root of 381564 is about 72.5307994387.

The spelling of 381564 in words is "three hundred eighty-one thousand, five hundred sixty-four".