1263257856 has 252 divisors, whose sum is σ = 4325202112. Its totient is φ = 360557568.

The previous prime is 1263257839. The next prime is 1263257857. The reversal of 1263257856 is 6587523621.

1263257856 is a `hidden beast` number, since 1 + 2 + 632 + 5 + 7 + 8 + 5 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (252).

Its product of digits (604800) is a multiple of the sum of its prime factors (1008).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1263257857) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 1305885 + ... + 1306851.

Almost surely, 2^1263257856 is an apocalyptic number.

1263257856 is a gapful number since it is divisible by the number (16) 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 1263257856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2162601056).

1263257856 is an abundant number, since it is smaller than the sum of its proper divisors (3061944256).

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

1263257856 is an frugal number, since it uses more digits than its factorization.

1263257856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1008 (or 979 counting only the distinct ones).

The product of its digits is 604800, while the sum is 45.

The square root of 1263257856 is about 35542.3389213484. The cubic root of 1263257856 is about 1081.0123840355.

The spelling of 1263257856 in words is "one billion, two hundred sixty-three million, two hundred fifty-seven thousand, eight hundred fifty-six".