263405478 has 64 divisors (see below), whose sum is σ = 619200000. Its totient is φ = 74666592.

The previous prime is 263405477. The next prime is 263405509. The reversal of 263405478 is 874504362.

It is a happy number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (263405473) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 306213 + ... + 307071.

It is an arithmetic number, because the mean of its divisors is an integer number (9675000).

Almost surely, 2^263405478 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 263405478, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (309600000).

263405478 is an abundant number, since it is smaller than the sum of its proper divisors (355794522).

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

263405478 is a wasteful number, since it uses less digits than its factorization.

263405478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1034 (or 1020 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 39.

The square root of 263405478 is about 16229.7713477424. The cubic root of 263405478 is about 641.0249511033.

The spelling of 263405478 in words is "two hundred sixty-three million, four hundred five thousand, four hundred seventy-eight".