18871212387 has 16 divisors (see below), whose sum is σ = 25538515200. Its totient is φ = 12393612000.

The previous prime is 18871212361. The next prime is 18871212391. The reversal of 18871212387 is 78321217881.

It is a happy number.

It is not a de Polignac number, because 18871212387 - 2¹⁸ = 18870950243 is a prime.

It is a super-2 number, since 2×18871212387² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18871212187) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 96189 + ... + 216782.

It is an arithmetic number, because the mean of its divisors is an integer number (1596157200).

Almost surely, 2^18871212387 is an apocalyptic number.

18871212387 is a deficient number, since it is larger than the sum of its proper divisors (6667302813).

18871212387 is a wasteful number, since it uses less digits than its factorization.

18871212387 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 313274.

The product of its digits is 301056, while the sum is 48.

The spelling of 18871212387 in words is "eighteen billion, eight hundred seventy-one million, two hundred twelve thousand, three hundred eighty-seven".