263481638616 has 640 divisors, whose sum is σ = 929605248000. Its totient is φ = 68037884928.

The previous prime is 263481638603. The next prime is 263481638627. The reversal of 263481638616 is 616836184362.

263481638616 is a `hidden beast` number, since 2 + 6 + 3 + 4 + 8 + 16 + 3 + 8 + 616 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

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 159 ways as a sum of consecutive naturals, for example, 169006045 + ... + 169007603.

It is an arithmetic number, because the mean of its divisors is an integer number (1452508200).

Almost surely, 2^263481638616 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 263481638616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (464802624000).

263481638616 is an abundant number, since it is smaller than the sum of its proper divisors (666123609384).

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

263481638616 is a wasteful number, since it uses less digits than its factorization.

263481638616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1693 (or 1680 counting only the distinct ones).

The product of its digits is 5971968, while the sum is 54.

The spelling of 263481638616 in words is "two hundred sixty-three billion, four hundred eighty-one million, six hundred thirty-eight thousand, six hundred sixteen".