8187718381 has 8 divisors (see below), whose sum is σ = 8670747384. Its totient is φ = 7704844800.

The previous prime is 8187718379. The next prime is 8187718403. The reversal of 8187718381 is 1838177818.

It can be written as a sum of positive squares in 4 ways, for example, as 2659052356 + 5528666025 = 51566^2 + 74355^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 8187718381 - 2¹ = 8187718379 is a prime.

It is a super-2 number, since 2×8187718381² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8187718681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 80031 + ... + 150931.

It is an arithmetic number, because the mean of its divisors is an integer number (1083843423).

Almost surely, 2^8187718381 is an apocalyptic number.

It is an amenable number.

8187718381 is a deficient number, since it is larger than the sum of its proper divisors (483029003).

8187718381 is a wasteful number, since it uses less digits than its factorization.

8187718381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77711.

The product of its digits is 602112, while the sum is 52.

The square root of 8187718381 is about 90486.0120736902. The cubic root of 8187718381 is about 2015.5224140762.

The spelling of 8187718381 in words is "eight billion, one hundred eighty-seven million, seven hundred eighteen thousand, three hundred eighty-one".