381171987 has 48 divisors (see below), whose sum is σ = 655479552. Its totient is φ = 216833760.

The previous prime is 381171971. The next prime is 381172009. The reversal of 381171987 is 789171183.

It is a happy number.

It is not a de Polignac number, because 381171987 - 2⁴ = 381171971 is a prime.

It is not an unprimeable number, because it can be changed into a prime (381171887) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 562693 + ... + 563369.

It is an arithmetic number, because the mean of its divisors is an integer number (13655824).

Almost surely, 2^381171987 is an apocalyptic number.

381171987 is a deficient number, since it is larger than the sum of its proper divisors (274307565).

381171987 is an equidigital number, since it uses as much as digits as its factorization.

381171987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1030 (or 1018 counting only the distinct ones).

The product of its digits is 84672, while the sum is 45.

The square root of 381171987 is about 19523.6263793384. The cubic root of 381171987 is about 725.0595191723.

It can be divided in two parts, 38117 and 1987, that added together give a palindrome (40104).

The spelling of 381171987 in words is "three hundred eighty-one million, one hundred seventy-one thousand, nine hundred eighty-seven".