218937681225 has 36 divisors (see below), whose sum is σ = 392169868272. Its totient is φ = 116758380000.

The previous prime is 218937681217. The next prime is 218937681229. The reversal of 218937681225 is 522186739812.

It is not a de Polignac number, because 218937681225 - 2³ = 218937681217 is a prime.

It is not an unprimeable number, because it can be changed into a prime (218937681229) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 4297150 + ... + 4347800.

It is an arithmetic number, because the mean of its divisors is an integer number (10893607452).

Almost surely, 2^218937681225 is an apocalyptic number.

218937681225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

218937681225 is a deficient number, since it is larger than the sum of its proper divisors (173232187047).

218937681225 is a wasteful number, since it uses less digits than its factorization.

218937681225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69878 (or 69870 counting only the distinct ones).

The product of its digits is 2903040, while the sum is 54.

The spelling of 218937681225 in words is "two hundred eighteen billion, nine hundred thirty-seven million, six hundred eighty-one thousand, two hundred twenty-five".