266289917465664 has 63 divisors (see below), whose sum is σ = 763273090862373. Its totient is φ = 88763175274752.

The previous prime is 266289917465651. The next prime is 266289917465681. The reversal of 266289917465664 is 466564719982662.

The square root of 266289917465664 is 16318392.

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

266289917465664 is a `hidden beast` number, since 2 + 6 + 6 + 2 + 8 + 9 + 9 + 1 + 7 + 46 + 566 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 36882300686400 + 229407616779264 = 6073080^2 + 15146208^2 .

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 8 ways as a sum of consecutive naturals, for example, 391301442 + ... + 391981374.

Almost surely, 2^{266289917465664} is an apocalyptic number.

266289917465664 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

266289917465664 is the 16318392-nd square number.

It is an amenable number.

266289917465664 is an abundant number, since it is smaller than the sum of its proper divisors (496983173396709).

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

266289917465664 is an frugal number, since it uses more digits than its factorization.

266289917465664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1359884 (or 679938 counting only the distinct ones).

The product of its digits is 11287019520, while the sum is 81.

The spelling of 266289917465664 in words is "two hundred sixty-six trillion, two hundred eighty-nine billion, nine hundred seventeen million, four hundred sixty-five thousand, six hundred sixty-four".