1263685728 has 24 divisors (see below), whose sum is σ = 3317175288. Its totient is φ = 421228544.

The previous prime is 1263685697. The next prime is 1263685733. The reversal of 1263685728 is 8275863621.

It is a tau number, because it is divible by the number of its divisors (24).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6581601 + ... + 6581792.

It is an arithmetic number, because the mean of its divisors is an integer number (138215637).

Almost surely, 2^1263685728 is an apocalyptic number.

It is an amenable number.

1263685728 is an abundant number, since it is smaller than the sum of its proper divisors (2053489560).

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

1263685728 is a wasteful number, since it uses less digits than its factorization.

1263685728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13163406 (or 13163398 counting only the distinct ones).

The product of its digits is 967680, while the sum is 48.

The square root of 1263685728 is about 35548.3575991916. The cubic root of 1263685728 is about 1081.1344184292.

The spelling of 1263685728 in words is "one billion, two hundred sixty-three million, six hundred eighty-five thousand, seven hundred twenty-eight".