264515804721 has 81 divisors (see below), whose sum is σ = 469446464331. Its totient is φ = 143085434688.

The previous prime is 264515804699. The next prime is 264515804747. The reversal of 264515804721 is 127408515462.

The square root of 264515804721 is 514311.

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

264515804721 is a `hidden beast` number, since 2 + 6 + 4 + 5 + 1 + 580 + 47 + 21 = 666.

It can be written as a sum of positive squares in only one way, i.e., 214590371121 + 49925433600 = 463239^2 + 223440^2 .

It is not a de Polignac number, because 264515804721 - 2¹⁹ = 264515280433 is a prime.

It is a super-2 number, since 2×264515804721² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (264515800721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 205209445 + ... + 205210733.

Almost surely, 2^264515804721 is an apocalyptic number.

264515804721 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

264515804721 is the 514311-st square number.

264515804721 is the 257156-th centered octagonal number.

It is an amenable number.

264515804721 is a deficient number, since it is larger than the sum of its proper divisors (204930659610).

264515804721 is an equidigital number, since it uses as much as digits as its factorization.

264515804721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2636 (or 1318 counting only the distinct ones).

The product of its (nonzero) digits is 537600, while the sum is 45.

The spelling of 264515804721 in words is "two hundred sixty-four billion, five hundred fifteen million, eight hundred four thousand, seven hundred twenty-one".