263894065840 has 40 divisors (see below), whose sum is σ = 645846006960. Its totient is φ = 100001961216.

The previous prime is 263894065811. The next prime is 263894065849. The reversal of 263894065840 is 48560498362.

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (263894065849) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 86805739 + ... + 86808778.

It is an arithmetic number, because the mean of its divisors is an integer number (16146150174).

Almost surely, 2^263894065840 is an apocalyptic number.

263894065840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

263894065840 is an abundant number, since it is smaller than the sum of its proper divisors (381951941120).

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

263894065840 is a wasteful number, since it uses less digits than its factorization.

263894065840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173614549 (or 173614543 counting only the distinct ones).

The product of its (nonzero) digits is 9953280, while the sum is 55.

The spelling of 263894065840 in words is "two hundred sixty-three billion, eight hundred ninety-four million, sixty-five thousand, eight hundred forty".