381366389 has 4 divisors (see below), whose sum is σ = 403799724. Its totient is φ = 358933056.

The previous prime is 381366367. The next prime is 381366397. The reversal of 381366389 is 983663183.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 325983025 + 55383364 = 18055^2 + 7442^2 .

It is a cyclic number.

It is not a de Polignac number, because 381366389 - 2¹⁶ = 381300853 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (381366889) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11216642 + ... + 11216675.

It is an arithmetic number, because the mean of its divisors is an integer number (100949931).

Almost surely, 2^381366389 is an apocalyptic number.

It is an amenable number.

381366389 is a deficient number, since it is larger than the sum of its proper divisors (22433335).

381366389 is a wasteful number, since it uses less digits than its factorization.

381366389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22433334.

The product of its digits is 559872, while the sum is 47.

The square root of 381366389 is about 19528.6043792177. The cubic root of 381366389 is about 725.1827610593.

The spelling of 381366389 in words is "three hundred eighty-one million, three hundred sixty-six thousand, three hundred eighty-nine".