218845260481 has 9 divisors (see below), whose sum is σ = 222520716873. Its totient is φ = 215229564720.

The previous prime is 218845260451. The next prime is 218845260493. The reversal of 218845260481 is 184062548812.

The square root of 218845260481 is 467809.

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

It can be written as a sum of positive squares in 4 ways, for example, as 494662081 + 218350598400 = 22241^2 + 467280^2 .

It is not a de Polignac number, because 218845260481 - 2⁵ = 218845260449 is a prime.

It is a super-2 number, since 2×218845260481² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (218845260451) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 28532515 + ... + 28540183.

It is an arithmetic number, because the mean of its divisors is an integer number (24724524097).

Almost surely, 2^218845260481 is an apocalyptic number.

218845260481 is the 467809-th square number.

218845260481 is the 233905-th centered octagonal number.

It is an amenable number.

218845260481 is a deficient number, since it is larger than the sum of its proper divisors (3675456392).

218845260481 is an frugal number, since it uses more digits than its factorization.

218845260481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15460 (or 7730 counting only the distinct ones).

The product of its (nonzero) digits is 983040, while the sum is 49.

Multiplying 218845260481 by its sum of digits (49), we get a square (10723417763569 = 3274663²).

The spelling of 218845260481 in words is "two hundred eighteen billion, eight hundred forty-five million, two hundred sixty thousand, four hundred eighty-one".