11781648 has 30 divisors (see below), whose sum is σ = 32972654. Its totient is φ = 3927168.

The previous prime is 11781647. The next prime is 11781659. The reversal of 11781648 is 84618711.

11781648 is a `hidden beast` number, since 1 + 1 + 7 + 8 + 1 + 648 = 666.

It can be written as a sum of positive squares in only one way, i.e., 6906384 + 4875264 = 2628^2 + 2208^2 .

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 (11781647) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 40765 + ... + 41052.

Almost surely, 2^11781648 is an apocalyptic number.

11781648 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

11781648 is an abundant number, since it is smaller than the sum of its proper divisors (21191006).

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

11781648 is a wasteful number, since it uses less digits than its factorization.

11781648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81831 (or 81822 counting only the distinct ones).

The product of its digits is 10752, while the sum is 36.

The square root of 11781648 is about 3432.4405311673. The cubic root of 11781648 is about 227.5457252212.

The spelling of 11781648 in words is "eleven million, seven hundred eighty-one thousand, six hundred forty-eight".