218617029225 has 243 divisors, whose sum is σ = 469516880079. Its totient is φ = 96954278400.

The previous prime is 218617029181. The next prime is 218617029263. The reversal of 218617029225 is 522920716812.

The square root of 218617029225 is 467565.

It is a perfect power (a square), and thus also a powerful number.

218617029225 is a `hidden beast` number, since 2 + 1 + 8 + 617 + 0 + 2 + 9 + 2 + 25 = 666.

218617029225 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 13 ways, for example, as 216110625129 + 2506404096 = 464877^2 + 50064^2 .

It is not a de Polignac number, because 218617029225 - 2¹⁷ = 218616898153 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is an unprimeable number.

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 242 ways as a sum of consecutive naturals, for example, 2994753789 + ... + 2994753861.

Almost surely, 2^218617029225 is an apocalyptic number.

218617029225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

218617029225 is the 467565-th square number.

218617029225 is the 233783-rd centered octagonal number.

It is an amenable number.

218617029225 is an abundant number, since it is smaller than the sum of its proper divisors (250899850854).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

218617029225 is an equidigital number, since it uses as much as digits as its factorization.

218617029225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 298 (or 149 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 45.

The spelling of 218617029225 in words is "two hundred eighteen billion, six hundred seventeen million, twenty-nine thousand, two hundred twenty-five".