1263964320 has 144 divisors (see below), whose sum is σ = 4358226600. Its totient is φ = 333545472.

The previous prime is 1263964309. The next prime is 1263964321. The reversal of 1263964320 is 234693621.

1263964320 is a `hidden beast` number, since 1 + 2 + 6 + 3 + 9 + 643 + 2 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1147583376 + 116380944 = 33876^2 + 10788^2 .

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (1263964321) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 135156 + ... + 144204.

Almost surely, 2^1263964320 is an apocalyptic number.

1263964320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1263964320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2179113300).

1263964320 is an abundant number, since it is smaller than the sum of its proper divisors (3094262280).

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

1263964320 is a wasteful number, since it uses less digits than its factorization.

1263964320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9167 (or 9156 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 36.

The square root of 1263964320 is about 35552.2758765174. The cubic root of 1263964320 is about 1081.2138615117.

The spelling of 1263964320 in words is "one billion, two hundred sixty-three million, nine hundred sixty-four thousand, three hundred twenty".