218532971986 has 16 divisors (see below), whose sum is σ = 374658286464. Its totient is φ = 93649404384.

The previous prime is 218532971981. The next prime is 218532972037. The reversal of 218532971986 is 689179235812.

It is not an unprimeable number, because it can be changed into a prime (218532971981) 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, 451110 + ... + 800353.

It is an arithmetic number, because the mean of its divisors is an integer number (23416142904).

Almost surely, 2^218532971986 is an apocalyptic number.

218532971986 is a deficient number, since it is larger than the sum of its proper divisors (156125314478).

218532971986 is a wasteful number, since it uses less digits than its factorization.

218532971986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1263945.

The product of its digits is 13063680, while the sum is 61.

The spelling of 218532971986 in words is "two hundred eighteen billion, five hundred thirty-two million, nine hundred seventy-one thousand, nine hundred eighty-six".