263998660864 has 81 divisors (see below), whose sum is σ = 560083991047. Its totient is φ = 124168896512.

The previous prime is 263998660853. The next prime is 263998660883. The reversal of 263998660864 is 468066899362.

The square root of 263998660864 is 513808.

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

263998660864 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 4 ways, for example, as 19757113600 + 244241547264 = 140560^2 + 494208^2 .

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 263998660864.

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, 139754832 + ... + 139756720.

Almost surely, 2^263998660864 is an apocalyptic number.

263998660864 is the 513808-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 263998660864

263998660864 is an abundant number, since it is smaller than the sum of its proper divisors (296085330183).

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

263998660864 is an frugal number, since it uses more digits than its factorization.

263998660864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3828 (or 1908 counting only the distinct ones).

The product of its (nonzero) digits is 161243136, while the sum is 67.

The spelling of 263998660864 in words is "two hundred sixty-three billion, nine hundred ninety-eight million, six hundred sixty thousand, eight hundred sixty-four".