381881749 has 4 divisors (see below), whose sum is σ = 391195980. Its totient is φ = 372567520.

The previous prime is 381881743. The next prime is 381881783. The reversal of 381881749 is 947188183.

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 64400625 + 317481124 = 8025^2 + 17818^2 .

It is a cyclic number.

It is not a de Polignac number, because 381881749 - 2¹⁹ = 381357461 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 (381881743) 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, 4657054 + ... + 4657135.

It is an arithmetic number, because the mean of its divisors is an integer number (97798995).

Almost surely, 2^381881749 is an apocalyptic number.

It is an amenable number.

381881749 is a deficient number, since it is larger than the sum of its proper divisors (9314231).

381881749 is an equidigital number, since it uses as much as digits as its factorization.

381881749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9314230.

The product of its digits is 387072, while the sum is 49.

The square root of 381881749 is about 19541.7949277951. The cubic root of 381881749 is about 725.5092729368.

It can be divided in two parts, 38188174 and 9, that added together give a palindrome (38188183).

The spelling of 381881749 in words is "three hundred eighty-one million, eight hundred eighty-one thousand, seven hundred forty-nine".